XPP math ub alignment problem

Solaris - XPP 8.4C.1 SP6

OK. I know I'm no longer supported but I have to ask the group this question.

I have a table with a column that has the default t4 rule turned on so that I can decimal align a column of numbers. Some rows have a value containing 4 digits, such as 99.99 and some rows have 2 digits such as 9.9. The column aligns correctly, however, if the cell with the 9.9 value has an "mt" math macro containing a "ub", then the underbar is not under the number but instead precedes it.

 

 99.99

__9.9

 

The coding for the 99.99 cell is: <Tc><chgcell;align;1>99.99

The coding for the 9.9 cell is: <Tc><chgcell;align;1><mt;sys><ub;;-25><bold>9.9<med><ubx><mx>

 

However, if a add 2 en spaces before the <mt> on the 9.9 cell, the underbar is under the number.

<Tc><chgcell;align;1>\n\n<mt;sys><ub;;-25><bold>9.9<med><ubx><mx>

 

Is this a known issue? Or what am I doing wrong? TIA.

Barry, Reed Tech