For versions < SPS 9 there is no build in feature available (that I know of) that would yield your desired result.
Regular expressions are there to accommodate exactly this kind of requirement.
So, if you want to do this ad hoc, within a SQL statement on SPS 8, you'll have to build this yourself.
Other than that, you may consider finding this via during data loading.
A last option that comes to my mind is to use text analysis with a custom configuration. Not sure if this is supported with SPS 8, though.
- Lars