PHP 5.0.0 Beta 1 : alternatives to MySQL?

OK, PHP 5.0 raises (or, better, it inherits from MySQL) a licence issues that hurts the people who develops commercial software on a open source platform so, which are the alternatives? PostgreSQL: is PGSQL LGPL'ed? (that is: is it possible to develop and sell commercial software without incourring in licence issues with PGSQL?) Firebird (ex Borland/Imprise Interbase): is Firebird LPGL'ed? Is there any other LPGL'ed RDBMS we should take into account? How about the old (and limited) mSQL? How about the (ghost-like) GNU SQL? How about Btrieve? Could this be the opportunity to switch to something more sophisticated, like an Object Oriented Database or a system designed since its beginning for DB replication and/or disconnected operations? (For example: how about the OODBMS "ZODB" used by Zope? How about Thor?) CU ---------------------------------- Alessandro Bottoni