phpBB (and I suspect more packages) which use database backends could not support entirely the dbx api. In some cases, it is required to disable dbx entirely. In php-sapi.eclass, dbx is compiled by default if use flags activates support for some form of db. This patch simply declares a private IUSE 'php-no-dbx', which will permit db support without dbx.
Created attachment 32439 [details, diff] php-sapi.eclass patch: dbx IUSE flag
rather than try to avoid the problem, lets see about fixing it. could you describe the problem you see with phpBB? (I don't use it myself)
configuration: php, mod_php, apache2, postgresql (latest stables in gentoo), phpBB Tried to change some use flag, but error remains: this is something like "The PHP configuration on your server doesn't support the {dat,source,database} On this offcial forum, I found phpBB does not support dbx: http://www.phpbb.com/phpBB/viewtopic.php?t=183882&highlight=#1039379 That lead to the suggestion to change the eclass: with 'php-no-dbx', all errors are gone. Alas, since i'm not a php guru, i don't know what is left behind without dbx abstaction api. I know gentoo forums are phpbb based. What do you use as backend?
just configure your phpBB to use mysql or postgres and not DBX.
