All,

Many thanks for the feedback, I have now played with and used the
<dyn:evaluate> function and it all does what I want.
However this only works when I run the XML through a PC based XSL transform
library (libxslt, saxon etc).

If I have XML that is being rendered in a Web Browser I don't have control
over the XSL library they use - is there
any way to easily get the same functionality in firefox / internet explorer
etc - As I dont think the browsers fully support
exslt yet?

Many thanks for the help
Daniel Laird