Here is an example of the function in action.
In this example we will be trying to put this around the date field:
WA_fieldValuesStr = "" & cStr(cStr(Request.Form("OrderReferenceID"))) & "" & "|" & "" & cStr(cStr(Request.Form("OrderVisitorID"))) & "" & "|" & "" & cStr(cStr(Request.Form("OrderShipping"))) & "" & "|" & "" & cStr(cStr(Request.Form("OrderTax"))) & "" & "|" & "" & cStr(cStr(Request.Form("OrderTotal"))) & "" & "|" & "" & cStr(cStr(Request.Form("OrderDate"))) & "" & "|"
So the code for the date field should be updated to look like this:
switchMonthDay(cStr(cStr(Request.Form("OrderDate")))) & "" & "|"
This code was taken from a DataAssist insert. I think it will do what you are looking for, please let us know if there are any problems with it.