dgettext vs. xgettext

Hi!

I'm using dgettext() with different domains in one set of scripts (or even
in one script). When extracting the messages with xgettext I would like to
specify an option to get only messages for one domain, like getting all
messages from calls to dgettext('foobar',...) and ignore all others.
Otherwise it wouldn't be possible to know which message belongs to which
domain. Did anyone else came across this problem? And, even more interesing:
Does anyone have a solution for this?

With kind regards
Thomas