After eating something and focusing my brain to something nicer than my
screens, I set some brackets and escaped the '.' with two '\' - now it
works. The condition now is:
condition = ${if and \
{ \
{match {$h_X-Spam-Flag:}{YES}} \
{> {${sg{$h_X-Spam-Score:}{\\.}{}}} \
{${lookup mysql{select users.sa_tag * 10 \
from users,domains \
where localpart = '${quote_mysql:$local_part}' \
and domain = '${quote_mysql:$domain}' \
and users.on_spamassassin = '1' \
and users.type = 'local' \
and users.domain_id=domains.domain_id } \
{$value}fail}} \
} \
} \
{yes}{no}}
Perhaps it will help somebody.
The SQL-Scheme is from Vexim