Hi, I'm using ColdFusion's reReplace() function for regular expression pattern replacement. I'd like to use a function call for the replacement string, and pass a matched backreference to it. Something like this: <cfset s = "STARTDATE_2010-05-07 00:05:00.0_ENDDATE" /> <cfset s = reReplace(s, "STARTDATE_([\s-.:0-9]*)_ENDDATE", dateAdd("h", 1, "\1")) /> But that fails because "The value of parameter 3, which is currently \1, must be a class java.util.Date value." Is there any other way to achieve this? Thanks, Stu