Stack trace()

I have a class that I use for database abstraction called DBAcess. I am calling various db functions like ora_parse, and am preceding with the @ operator. If the call fails, the error message is set in php_errormsg, which is cool, but there are two things missing. Firstly the line number of the error, and secondly a stack trace of the error. Is there any way to access these things. I also noticed that if I remove the @, I still don't get a stack trace. Iam using php4.0.0 compile with --enable-track-vars --with-oci8 --with-oracle and Oracle 8.0.5.1 on RedHat 6.2. Is there any way to get a stack trace. Is there a flag in the php.ini file that I need to set? Alex