Here is the DIFF between working version and brocken version. Maybe this could help to fix the buf

Index: oci8.c
===================================================================
RCS file: /repository/php4/ext/oci8/oci8.c,v
retrieving revision 1.177
diff -r1.177 oci8.c
1247c1247
<       if ((! statement->has_data) || (column->indicator == -1)) { /* column is NULL or statment has no current data */
---
>       if (column->indicator == -1) { /* column is NULL */
1395d1394
< 
1397d1395
<       statement->has_data = 0;
1673,1680c1671
<                                       if ((outcol->data_type == SQLT_DAT) || (outcol->data_type == SQLT_NUM)
< #ifdef SQLT_TIMESTAMP
<                                               || (outcol->data_type == SQLT_TIMESTAMP)
< #endif
< #ifdef SQLT_TIMESTAMP_TZ
<                                               || (outcol->data_type == SQLT_TIMESTAMP_TZ)
< #endif
<                                          ) {
---
>                                       if ((outcol->data_type == SQLT_DAT) || (outcol->data_type == SQLT_NUM)) {
1781d1771
<               statement->has_data = 0;
1841,1842d1830
<               statement->has_data = 1;
< 
1849,1850d1836
<       statement->has_data = 0;
< 
3745,3754d3730
< #ifdef SQLT_TIMESTAMP
<               case SQLT_TIMESTAMP:
<                       RETVAL_STRING("TIMESTAMP",1);
<                       break;
< #endif
< #ifdef SQLT_TIMESTAMP_TZ
<               case SQLT_TIMESTAMP_TZ:
<                       RETVAL_STRING("TIMESTAMP_TZ",1);
<                       break;
< #endif
4254,4255c4230,4231
<       text errbuf[512];
<       sb4 errcode = 0;
---
>     text errbuf[512];
>     sb4 errcode = 0;
4258,4261d4233
< #ifdef HAVE_OCI8_ATTR_STATEMENT
<       ub2 errorofs = 0;
<       text *sqltext = NULL;
< #endif
4268,4286d4239
< 
< #ifdef HAVE_OCI8_ATTR_STATEMENT
<                       CALL_OCI_RETURN(statement->error, OCIAttrGet(
<                               (dvoid *)statement->pStmt,
<                               OCI_HTYPE_STMT,
<                               (text *) &sqltext,
<                               (ub4 *)0,
<                               OCI_ATTR_STATEMENT,
<                               statement->pError));
< 
<                       CALL_OCI_RETURN(statement->error, OCIAttrGet(
<                               (dvoid *)statement->pStmt,
<                               OCI_HTYPE_STMT,
<                               (ub2 *)&errorofs,
<                               (ub4 *)0,
<                               OCI_ATTR_PARSE_ERROR_OFFSET,
<                               statement->pError));
< #endif
< 
4321,4324d4273
< #ifdef HAVE_OCI8_ATTR_STATEMENT
<               add_assoc_long(return_value, "offset", errorofs);
<               add_assoc_string(return_value, "sqltext", sqltext ? (char *) sqltext : "", 1);
< #endif
Index: php_oci8.h
===================================================================
RCS file: /repository/php4/ext/oci8/php_oci8.h,v
retrieving revision 1.24
diff -r1.24 php_oci8.h
122d121
<       int has_data;

Example to reproduce, copied from the manual:

<?php
/* OCIDefineByPos example thies@thieso.net (980219) */

$conn = OCILogon("scott","tiger");

$stmt = OCIParse($conn,"select empno, ename from emp");

/* the define MUST be done BEFORE ociexecute! */

OCIDefineByName($stmt,"EMPNO",&$empno);
OCIDefineByName($stmt,"ENAME",&$ename);

OCIExecute($stmt);

while (OCIFetch($stmt)) {
    echo "empno:".$empno."\n";
    echo "ename:".$ename."\n";
}

OCIFreeStatement($stmt);
OCILogoff($conn);
?>

The first result row is empty, subsequent ones are ok.

This bug has been fixed in CVS.

In case this was a PHP problem, 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/.
 
In case this was a documentation problem, the fix will show up soon at
http://www.php.net/manual/.

In case this was a PHP.net website problem, the change will show
up on the PHP.net site and on the mirror sites in short time.
 
Thank you for the report, and for helping us make PHP better.