Many moons ago I worked for ISOKON (then Eleetix Software) who I know had an interest in investment management software. Not sure what they are up to now but you could try calling Gregory van Dyk Watson on 020 7485 9909 (please mention my name if you would).
Ian Digby, Hampshire.
I work as a business analyst for DST Global Solutions one of the companies mentioned in the list above.
The product we have providing comprehensive investment accounting functionality is HiPortfolio/3. There is lots more information on HiPortfolio on our website or you are very welcome to contact us also via the website.