[Groff] Bold \(sq not filled

[carsten . kunze]

Hello,

in troff the Times Roman Bold \(sq is filled solid black. In groff there is no 
difference between any Times Roman font.

Is there a way to get the standard (UNIX V7) behaviour of a solid filled bold 
\(sq?

(I also checked heirloom troff, there bold \(sq is as expected.)

Or is there any other special character which draws a solid filled square? (At 
the moment I use a scaled draw function.)

Regards,
Carsten