EIDW_Pilot>
I know it is possible to use a south african ppl in europe
Careful - assuming you mean in non-SA registered aircraft, you have to approach this country by country - it's true for the UK that you can use the private (and only private) privileges of SA licences in the UK without further legal formality in UK registered aircraft - providing your SA licence is fully valid for the flight. (eg: in date, correct type, medical valid, etc). This does not mean the same rule applies for each European country - they all have their own validation rules, although presumably you've confirmed with the Eire authorities that they follow the UK in that respect, but it is not exactly common in Europe. For UK only, you can look at the UK CAA FAQ site for confirmation of foreign licence privileges:
UK CAA FAQ on ICAO Licences
As you mention IMC ratings, remember this is a UK rating for UK airspace and is only attached to a UK CAA or JAA licence, so it can't be attached to a SA PPL. The closest you can get to UK IMC privileges (as a SA PPL holder for use in UK registered aircraft) is a SA I/R on your SA PPL - but even then a 'foreign' (eg: SA) I/R it will not cover you for IFR operation in UK controlled airspace. (See that CAA link above).
There is now a UK SA Flyer Community forming with its own webpage to keep SA PPLs in touch with any others locally and FAQs for SA privileges, UK based SA medical examiners, news, free advice, fly-ins, shared experiences, etc) - I'll check with the moderators that I can put the link up here then do so if it's ok - however, you can get the link by mailing me if you want it.