sed - OSS problems

I've been trying to compile various pieces of open source (mainly C)
software on the iSeries. For example, libxml, libxslt, ruby amongst
others.. 

Each of these packages has a 'configure' script that you run as part of
the build process. However in all cases the configure script errors when
it tries to run sed commands in QSHELL. The error is usually along the
lines of 'error with regular expression: \( \) or ( ) imbalance..'

When you look at the source there does not seem to be a problem with the
expressions, despite the error message indicating that there are missing
or extraneous parentheses.. 

Is there a difference between sed in QSHELL, and sed in *nix
implementations that may be causing this? Has anyone built any of these
types of open source packages on iSeries successfully? 

Regards,
Stu

Stuart Bramley
Technical Architect
Skandia::GroupIT
t: 023 80 72 64 29
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