Sage software is a UK company who produce accounting applications and over the years they have grown to dominate the market place - Sage has become almost the 'De Facto' standard for UK accountants. This is a bad situation in my opinion, however ....
I have several clients who are accountants and who run Sage and pay for a 'networked version' - this is a really a simple file share for centralised data and client software looks to the network path.
Current and past version of SME have worked in this scenario.
Some time ago Sage software bought a Contact Management software called ACT! - I think it used to belong to Symantec, and some else previous to that. Anyway, as usual with most office apps ACT! got bigger and bigger all the time and it now installs a 'local version' of SQL server on each client machine even though the data for the network version resides on a network drive.
After spending many hours trying all sorts of tricks to get ACT! to run with data residing on SME ibay I gave up. ACT! 'knows' SME is not Windows and everything I tried failed.
Support for ACT! is very sketchy indeed (Sage Accounting support is going the same way, surprise surprise!) and whilst you can occasionally talk to a sensible tech most back off as soon as you mention Linux. Application support is even worst, its such a hotch potch of departments etc.
So, I have ended up with SME for everything but ACT! and put a small box with W2K on for up to 10 ACT! users max, more than that and you are forced to go with M$ SQL server on SBS or 2003S.
Another accounting application worth mentioning is IRIS which is more of an accounants practice management software. IRIS will currently run on SME but the updates wont. You have to move all the data to a Winstation, perform the update there, then move it back to the SME again. IRIS tech say off the record that they know they have some customers using Linux but dont officially support it, in fact they discourage it ... "If we cant reproduce the problem we cant help you" (so get a Linux box then and make a start - some hope) In any case IRIS have officially announced that in the next year to two years IRIS will require M$ SQL and wont work without it. So, pay up or go elsewhere. When you look at the IRIS site now there is M$ Partnership logo's on it !!!
Out of interest it might be useful to have a list somewhere of different apps people have gotten working, any special tweaks on SME etc.
Just a thought ...