[Striat]

To fix this in perlparser.cpp

XS(XS__setguild);
XS(XS__setguild)
{
	dXSARGS;
	if (items != 2)
		Perl_croak(aTHX_ "Usage: setguild(new_guild_id, new_rank)");

		unsigned long		new_guild_id = (unsigned long)SvUV(ST(0));
	char	new_rank = (char)*SvPV_nolen(ST(1));

	quest_manager.setguild(new_guild_id, new_rank);

	XSRETURN_EMPTY;
}

Change:

char	new_rank = (char)*SvPV_nolen(ST(1));

To:

int	new_rank = (int)SvIV(ST(1));

Recompile and you should be good to go.