I think this is a bug with PHP. Every now and then I will get connection errors when connection to an Oracle 8 database running on Irix. We do not get these errors when working with Perl, and we have substatialyl increased the number of simultaneous connections allowed, with no success.

(If we need to upgrade PHP to get rid of this error, please let us know).

an example of the error:
Warning: oci8_open_server: ORA-12541: TNS:no listener in include/init.inc on line 11

some info from phpinfo():

OCI8
                           Oracle version: 
                           Compile-time ORACLE_HOME: 
                           Libraries used: 
              Oracle
                           Oracle version: 
                           Compile-time ORACLE_HOME: 
                           Libraries used: 
              Apache
                           APACHE_INCLUDE=
                           APACHE_TARGET=
                           Apache Version: Apache/1.3.12
                           Apache Release: 10312100
                           Apache API Version: 19990320
                           Hostname/port: www.umbc.edu:80
                           User/Group: umbcwww(115)/60001
                           Max Requests: per child: 1000    keep alive: off    max
                           per connection: 100
                           Timeouts: connection: 30    keep-alive: 1
                           Server Root: /afs/umbc.edu/admin/www/umbc
                           Loaded modules: UMBC::WebAuthDBM, mod_perl,
                           mod_php3, mod_setenvif, mod_auth, mod_access,
                           mod_alias, mod_userdir, mod_actions, mod_imap,
                           mod_asis, mod_cgi, mod_dir, mod_autoindex,
                           mod_include, mod_status, mod_negotiation, mod_mime,
                           mod_log_config, mod_env, http_core