InfoPath Dev

I have an InfoPath form that work perfectly against a web service in "Preview Mode" but, when I run the design checker and use the "Verify on Server" I get an error message that says, The following expression could not be parsed because of a syntax error or because it uses an undefined namespace prefix or unsupported function: translate(concat(floor((sum(xdMath:Eval(../dfs:dataFields/tns:retrieveTimesheetsResponse/tns:retrieveTimesheetsResult/q1:ts/q1:timeStop, 'substring-before(., ":")')) * 60 + sum(xdMath:Eval(../dfs:dataFields/tns:retrieveTimesheetsResponse/tns:retrieveTimesheetsResult/q1:ts/q1:timeStop, 'substring-after(., ":")')) - (sum(xdMath:Eval(../dfs:dataFields/tns:retrieveTimesheetsResponse/tns:retrieveTimesheetsResult/q1:ts/q1:timeStart, 'substring-before(., ":")')) * 60 + sum(xdMath:Eval(../dfs:dataFields/tns:retrieveTimesheetsResponse/tns:retrieveTimesheetsResult/q1:ts/q1:timeStart, 'substring-after(., ":")')))) div 60), format-number((sum(xdMath:Eval(../dfs:dataFields/tns:retrieveTimesheetsResponse/tns:retrieveTimesheetsResult/q1:ts/q1:timeStop, 'substring-before(., ":")')) * 60 + sum(xdMath:Eval(../dfs:dataFields/tns:retrieveTimesheetsResponse/tns:retrieveTimesheetsResult/q1:ts/q1:timeStop, 'substring-after(., ":")')) - (sum(xdMath:Eval(../dfs:dataFields/tns:retrieveTimesheetsResponse/tns:retrieveTimesheetsResult/q1:ts/q1:timeStart, 'substring-before(., ":")')) * 60 + sum(xdMath:Eval(../dfs:dataFields/tns:retrieveTimesheetsResponse/tns:retrieveTimesheetsResult/q1:ts/q1:timeStart, 'substring-after(., ":")')))) mod 60, ":00")), "aN", ""). Any ideas?

Its likely that one of the functions is simply not supported on the server.  Try breaking down your formula to only include one function at a time then publish.  Keep adding functions until it breaks.  That will help narrow down that pesky function.  Good luck!

I'm surprised there isn't a list of functions not supported on the server available on the web anywhere (at least not that I've found).