I am also experiencing this very problem. The mail will not arrive at my BB until after 7 minutes of it originally popping up on my screen.
I have upgraded to the premium hotmail account so I would be able to send and receive my hotmail messages onto my BB.

At the time of setting up the e-mail account on my BB, I also created a new BB one which is @02email.co.uk - do I even need this or shall I just delete it?
This address is under default services for 'Calendar (CICAL)' and 'Messaging (CMIME)'. I'm wondering if I should change this with my hotmail address as primary?

I also looked for the settings that the original poster has changed "the "mailbox conflicts" option, "handheld wins". " - but I could not find this on my BB.

If this is the norm for hotmail would it be worthwhile creating a gmail/yahoo account and then arrange for any hotmail messages to be auto forwarded to gmail/yahoo?

I seem to have to send my service books quite often, even though it's only be working just over a day!

Thanks in advance for your advice.