beamed grace stem length

[Stan Sanderson]

Yes, I know it's an old question. I've looked at the posts, gone to  
the manual, but haven't found anything that works. I'm stuck.

%%%%%%%%%%%%
\version "2.10.16"
\paper { ragged-right = ##t }
\relative c'' {
\time 3/8
\stemUp
a8 c e | d[ \appoggiatura { c16[ d]} c8 b]
}
%%%%%%%%%%%%%

produces the output in the attached pdf.

The appoggiatura beamed stems are too long.

If a simple answer exists, please help!

Stan