I thought I should post in case anyone else has a similar issue. After recent upgrade of script I could no longer connect to the database. Nothing changed except upgraded script. Reason, not sure, but, thinking host issue. Anyway, my simple fix was to simply create a NEW database user and more secure pass for that user. I've had to do this on a couple site scripts that suddenly stopped working for no apparent reason. And my host now requires more secure database passwords.
Stats (in case it helps)
PHP5 (never had problems getting the script to work on it, even before updating from php4, so may be a simple fix for those having an issue)
script version of recent upgrade 3.2.9
Hope it helps!