Q: defining classes from shell command output

[jmw]

I'm trying to define a class using the out put of a shell command eg:
control:
        bits = ( "exec /usr/bin/isainfo -kv | cut -b1-2" )
        addclasses  =  ( "$(bits)" )

This should presumably add a class called "32" or "64".

Instead I get classes that are  the actual shell command  - not the 
output of the shell command.

Perhaps there is a cleaner  way to create a class based on the kernel 
arch...

Thanks!

BTW - using  cfengine 1.6.3 on solaris 7 & 8 machines