roman numerals in VB6

Could someone please send me code or help for a program in VB6 that converts roman numerals to numbers? It has to be able to handle combinations like XIII and no when a numeral is invalid like XCI. I have been having trouble with this for a while, and I need it for a class I am currently holding a D in. Please respond quickly if you can, it's due the week of March 29th.

[Uranium-235]

this might help a little

http://vbnet.mvps.org/code/helpers/numbertotext.htm

[Dragon]

the trick is to use a function similar to charAt in java.. its been awhile since ive written VB, but you have to look at groups of 2 symbols id think.