Stacked Fractions not displaying in Edited Dimension Text

It is common practice to edit dimension text such as changing " 10'-10" "to "MIN 10½ FT CLEAR". When editing the dimension text of an existing dimension element (using Edit Text), typed stacked fractionssuch as 1/8, 3/16, etc. are replaced with a “?”. However, fractions ½, ¼, and ¾ all work fine.

The question marks appears only when all three of these conditions exist:
• The font is a Bentley "stick" font (Engineering, Working, etc)
• The fraction is stacked
• The font contains fractions for 8ths, 16ths, 32nds, and 64ths

However, the fraction displays correctly:
• When the fraction is not stacked OR
• When ANY stacked fraction other than 8ths, 16ths, 32nds, or 64ths is done in Bentley fonts. (i.e. 13/100 works fine)
• When ANY stacked fraction is done in TrueType fonts

Is this a bug?  Running MicroStation CE 10.10.00.23.