Can a drop-down list have rich text formatting?

I want a drop down list to have choices that include bold AND normal text.  It seems this can be done for the caption, but I can't get it to work for the values.  Can this be done using the XML Source code?  Below is an example of what I want the choices to look like.

1. You increased your payment.

2. You decreased your payment.

Thanks for your help.

Mike