[BioC] How do I install custom made CDF in Bioconductor

[Ruppert Valentino]

Hello,
         I have created a custom made CDF file and am trying to install that 
to analyse Affymetrix chip files. Can anyone tell me what format should the 
CDF files be in? and when does the CEL file has a CDF file attached to it, 
if so how can I update the CEL file data with my custom made CDF?

Many thanks

Raphael.