Kevin,
Follow-up, I misspoke, sorry - if you don't specify an sqldbtype, the default for a string is an NVarChar. I thought it was text, but it's NVarChar. So given your database, I don't think it's necessary to do what I suggested last night.
As for the runtime error - I'm out of clues at this point. You might want to consider stepping through the code with the debugger, and examine the two parameter objects (oParms) right before the query runs. Check certain properties of the two param objects, such as the value, the parameter name, sqldbtype, etc. I'll look at the code you posted again to see if I can think of anything else, but for now that's all I can come up with.
Kevin