I struggled getting my exchnge mail on my personal BB as well. I finally found a good work around.
I use the Out of Office Assistant from Outlook. I setup the assistant to believe I am always out of the office and then have it forward my email to a gmail account that I use only for my work email.
There were a few settings I had to get right, but it works and I get my emailsalmost as fast as they come into my computer.
It is not perfect, if I reply the message does come from my gmail account. But this isn't a huge problem, for me.