I sell an addin which links to a number of real time providers (eSignal,
market feed...) using a dll (written to the RTD standard). I use VBA
wrapper functions which in turn call the RTD dll. Works fine with Excel 2002
and Excel 2003. It does NOT work with Excel 2007 however. I've recompiled
the dll to ensure the VB 6.0 reference includes the 2007 libraries. If I use
the RTD function directly from a worksheet cell it DOES work. This shows the
dll is functioning correctly. However, when it's included in a VBA wrapper
function nothing happens. ie cell values are not updated. I've stipped the
dll down to the point where it simply displays the time -- ie a few lines of
code -- with the same result: wrapper functions do not work.

Wrapper functions are essential as asking users to use RTD direct is complex
and not a practical solution for average users. Has anybody else had a
problem with wrapper fucntions?