I have also found this to occur on PHP 5.0.5, also on Gentoo.

I've narrowed it down, I think.
Relevant excerpts from the WSDL:

<s:element name="ProvisionMonitors">      
 <s:complexType>
   <s:sequence>
    <s:element minOccurs="0" maxOccurs="1" ref="ProvisioningOrder" />
   </s:sequence>
 </s:complexType>
</s:element>

<s:element name="ProvisioningOrder" type="ProvisioningOrder" />
<s:complexType name="ProvisioningOrder">
 <s:complexContent mixed="false">
  <s:extension base="CServiceObject">
   <s:sequence>
    <s:element minOccurs="0" maxOccurs="1" name="MonitorOrders" type="ArrayOfMonitorOrder" />
    ...
   </s:sequence>
   <s:attribute name="name" type="s:string" />
   ...
  </s:extension>
 </s:complexContent> 
</s:complexType> 

No "name" is specified in the upper block of XML, for the line with the "ref=". If I specify a name the WSDL parses. I believe the correct behavior would be for PHP to acquire the name from the complexType declaration. I don't know if this should always be the case for references, or only when no name is provided - if providing a name is even valid for them.

This is just a guess, though. I've dealt very little with references so do not know the standards surrounding them; only what digging into the XML has revealed.

Please try using this CVS snapshot:

  http://snaps.php.net/php5.2-latest.tar.gz
 
For Windows:

  http://windows.php.net/snapshots/

No feedback was provided for this bug for over a week, so it is
being suspended automatically. If you are able to provide the
information that was originally requested, please do so and change
the status of the bug back to "Open".

Having the same problem happening with a valid WSDL on php 5.2.5 and 5.2.6, I tested it on the latest snapshot of PHP (5.2.7RC6) and got the same error.

Hope it helps.

having the same problem. Urgent fix needed!

follow extract of the WSDL

<s:element name="getLinkProfilesByTicketResponse">
        <s:complexType>
          <s:sequence>
            <s:element minOccurs="0" maxOccurs="1" ref="getLinkProfilesByTicketResult" />
          </s:sequence>
        </s:complexType>
      </s:element>

.....


      <s:element name="getLinkProfilesByTicketResult" type="LINKPROFILESRESPONSE" />
      <s:complexType name="LINKPROFILESRESPONSE">
        <s:sequence>
          <s:element minOccurs="0" maxOccurs="1" name="USER" type="USER" />
        </s:sequence>
        <s:attribute name="error" type="s:string" />
      </s:complexType>
      <s:complexType name="USER">
        <s:sequence>
          <s:element minOccurs="0" maxOccurs="1" name="CODMARKET" type="s:string" />
          <s:element minOccurs="0" maxOccurs="1" name="USERNAME" type="s:string" />
          <s:element minOccurs="0" maxOccurs="1" name="SINCOM" type="s:string" />
          <s:element minOccurs="0" maxOccurs="1" name="LOGINNAME" type="s:string" />
          <s:element minOccurs="0" maxOccurs="1" name="FIRSTNAME" type="s:string" />
          <s:element minOccurs="0" maxOccurs="1" name="LASTNAME" type="s:string" />
          <s:element minOccurs="0" maxOccurs="1" name="EMAIL" type="s:string" />
          <s:element minOccurs="0" maxOccurs="1" name="TELEPHONE" type="s:string" />
          <s:element minOccurs="0" maxOccurs="1" name="FAX" type="s:string" />
          <s:element minOccurs="0" maxOccurs="1" name="USERTYPE" type="s:integer" />
          <s:element minOccurs="0" maxOccurs="1" name="COMPANY" type="s:string" />
          <s:element minOccurs="0" maxOccurs="1" name="SAPUSERID" type="s:string" />
          <s:element minOccurs="0" maxOccurs="1" name="MAINSINCOM" type="s:string" />
          <s:element minOccurs="0" maxOccurs="1" name="STATUS" type="s:integer" />
          <s:element minOccurs="0" maxOccurs="1" name="LANGUAGE" type="s:string" />
          <s:element minOccurs="0" maxOccurs="1" name="APPLICATIONS" type="ArrayOfAPPLICATION" />
        </s:sequence>
      </s:complexType>
      <s:complexType name="ArrayOfAPPLICATION">
        <s:sequence>
          <s:element minOccurs="0" maxOccurs="unbounded" name="APPLICATION" type="APPLICATION" />
        </s:sequence>
      </s:complexType>
      <s:complexType name="APPLICATION">
        <s:sequence>
          <s:element minOccurs="0" maxOccurs="1" name="ROLE" type="s:string" />
          <s:element minOccurs="0" maxOccurs="1" name="BRANDS" type="s:string" />
        </s:sequence>
        <s:attribute name="name" type="s:string" />
        <s:attribute name="market" type="s:string" />
        <s:attribute name="enabled" type="s:integer" />
      </s:complexType>
      <s:element name="LINKPROFILESRESPONSE" type="LINKPROFILESRESPONSE" />

Hi,

I'm having the same problem... And it's a bit tough for me to troubleshoot because I'm using a file package provided by a website.

http://www.nena.org/xml_schemas/NENAFiles/CurrentNENA/CurrentNENA.zip

I'm trying to get the validateAddress to work (from the v7 interface) but so far no luck! I'm stuck on this undefined ref variable.....

Is anyone looking into this?  I'm having the same issue on
Ubuntu 8.10 with PHP 5.2.6-2 when trying to parse a .net web service

WSDL:http://d2c.9squared.com/f/ContentRetrieval.asmx?WSDL

Same here. Test files available at

http://dev.profi.it/ota.zip

Please review this issue! Thanks a lot!

Same error connecting to .net service with PHP 5.2.13 and PHP 5.2.14RC2

Try it with, for example :

$url = "http://d2c.9squared.com/f/ContentRetrieval.asmx?WSDL";
$soapClient = new SoapClient($url array('soap_version' => SOAP_1_2));


will result in

[WSDL] SOAP-ERROR: Parsing Schema: unresolved element 'ref' attribute.

Also not working in php5.3 it seems. Why is this bug not being picked up? It kind of defeats the purpose if I have to store WSDL files locally... and even worse, also have to change/add name= to the file.

I'm having the same problem consuming OTA (Open Travel Alliance) XML files, using php5.3.3 on Ubuntu.
Does anyone know a fix or a workaround?

Im am experiencing the same problem with a .NET webservice using the 'ref' attribute in the WSDL.

PHP version 5.3.6

Also experiencing the issue with PHP 5.3 using the OTA ( Open Travel Alliance  ) WSDL.  Honestly if this has been an issue since 5.0.5, it should be fixed by now.  Adding name="name" in front of ref=" in all of the XSD's allows the parser to succeed but it technically is an invalid WSDL.  I hope there is a real fix for this glaring WSDL parsing bug soon.

This bug has been fixed in SVN.

Snapshots of the sources are packaged every three hours; this change
will be in the next snapshot. You can grab the snapshot at
http://snaps.php.net/.

 For Windows:

http://windows.php.net/snapshots/
 
Thank you for the report, and for helping us make PHP better.

just a heads up everyone: most of these issues can be resolved by changing 

<xs:include schemaLocation="Schema_File.xsd"/>

to 

<xs:import schemaLocation="Schema_File.xsd"/>

you will of course need to be using local WSDL/XSD files, which shouldn't be a problem for OTA requests.

Still getting

SOAP-ERROR: Parsing Schema: unresolved element 'ref' attribute

whith PHP 5.3.14 (cli) (built: Jun 19 2012 03:47:42) on CENTOS

while parsing a WSDL containing 

<xs:attributeGroup ref="TelephoneInfoGroup">
<xs:annotation>
<xs:documentation source="Description" xml:lang="en">
Information about a telephone number, including the actual number and its usage.
</xs:documentation>
</xs:annotation>
</xs:attributeGroup>

removing ref= and replacing with name= solves the problem but this fix cannot be applied on remote WSDL and leads to potentially invalid WSDL

In case this WSDL file doesn't contain an attributeGroup with name="TelephoneInfoGroup" it's definitely wrong WSDL.

You may provide a complete WSDL/XSD example to prove if it's a bug in ext/soap.

I've committed an additional fix into PHP-5.4 and above

it's still ocurrs from a external wsdl on php 8.0.3
$client = new \SoapClient($wsdl, $params); return SOAP-ERROR: Parsing Schema: unresolved group 'ref' attribute