insert a pdf in my lyx doc

[Richard Brown]

I've found a number of posts that say the best way to insert a pdf file
is to use 
Insert > File > External material 
and choose the pdf template option.

However, when I do this I only get chess, lily pond and raster templates
offreed. I read somewhere that I need to update the includepdf package
if I get this problem- but I haven't a clue how to do that. Can someone
give me a pointer? Thanks!

I'm running lyx 1.5.3 on ubuntu 8.04 

TIA

Richard