~ disappears in postscript

[Bruce Richardson]

I'm writing a LinuxDoc document using Lyx 1.1.4fix3.  If I export the
document to postscript, any ~ character in a code environment disappears.
Since I'm using a lot of command line examples, this isn't ideal!  Any
clues?

-- 
Bruce

It is impolite to tell a man who is carrying you on his shoulders that
his head smells.