Hi Kostya, just came across AquaMail, looks very good but we will need MS Exchange support very soon as older installations are upgraded to newer ones... your forum seems repleat with users who are forced to drop IMAP access and use only Exchange.
I know you are a one man team... but do the maths..... you can charge at least 3 times more than your pro key price for an MS Exchange version plus you also support multiple other IMAP/POP accounts. That's a great USP, "unique selling point"
WHICH MEANS YOU CAN TAKE ON ANOTHER SOFTWARE PERSON TO DO THE DEVELOPMENT!!
every blessing