Informix user wierdness

This is more an Informix question rather than a PHP question but I hope someone can help I've installed the Linux-SE version and CSDK of Informix from informix.com and installation has gone fine including createing the demo DB. I can also start 'dbaccess' and browse/query the tables so the envvars seem fine. However, when I endeavour to use the PHP functions, I get an error in ifx_connect() I constantly get the error: E [SQLSTATE=IX 000 SQLCODE=-952] User ()'s password is not correct for the database server. Note how the username field is empty. What's the procedure for 'logging in' to the DB? I created the demo DB as a normal user and I've read that the user auth stuff is done through the operating system. Using 'dbaccess' to try and connect to the DB as the same user rather then starting dbaccess in the DB dir causes the same error to occur so it's obviously something in the setup. My sqlhosts line is 'demo_se seipcpip dev sqlexec' and the ifx_connect line is 'ifx_connect("stores7@demo_se", "testuser", "mypasswd")' Cheers, Graeme