Almost all of the central and western European countries are currently in the process of converting to the Euro (a common European currency).
Conversion to a country's currency that is transitioning to the Euro must be done via "triangulation", which means going through the Euro. For example, in order to convert German marks to US dollars.  Conversion rates between currencies are not symmetric so short-cuts may not be taken (a simple, non-Euro example: the currency conversion rate from US dollars to Japanese yen may be 2 to 1, but the conversion rate from yen to dollars may be 1 to 3  ''Man...2-3 yen.  Has the dollar fallen '''that''' far??? :) ''.  After a transition period of several years, all of the participating countries will deal exclusively with the Euro.

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As far as software fixes go, I imagine this is at least as difficult as y2k date conversions and fixes for financial and banking software.  It seems that things are doing well in light of this fact --AlanHecht