[exim] Problem with String expansion in nested conditions?

Hi.

I'm trying to build a condition for running SA-Exim.

Doing so I'm in need of nesting conditions.

The following condition works fine, without
"{!eq {$header_X-SA-Do-Not-Run:}{Yes}}".
Adding the line above, I get a "PANIC: SAEximRunCond expansion failure
on..." :-(

Many thanks for any upcoming ideas!

Regards,

Maximilian



My condition (minimized to reproduce the error):

SAEximRunCond: ${if or {
  {match{{$h_Received:}{fetchmail}}}
  {and {
    {def:sender_host_address}
    {!def:authenticated_sender}
    {!eq {$header_X-SA-Do-Not-Run:}{Yes}}
         }
  }
} {1}{0} }