Logging in to mail from BlackBerry - login error

[#1]

When I navigate to the login page using my Blakberry I eneter exactly the same details as I do normally,  e.g. my username my password and select Plusnet from the drop down. But I get an error:
ERROR
Unknown user or password incorrect
Go to the login page
I'm definitely putting in the exact same details as when I log in from my PC, so what am I doing wrong?

[#2]

Hi,
I'm not really sure what to suggest I'm afraid.  I don't have a blackberry, but I did just try logging on using my iPhone and it worked fine.
Has anyone else come across a similar problem?

[#3]

I've also just tried on my HTC Hero and no problems whatsoever - have you tried changing your mailbox password to something really simple temporarily in order to make sure it's not a text input issue?
Other than that, I'm not too sure what to suggest.

[#4]

I'm having exactly the same problem  - did you get this sorted?I can log in but then when I go to log in to webmail (always wondered why one has to log in twice...) I get an error message  - firstly saying 'you must be logged in to do that'  - when /I am logged in....
and then on subsequent attempts log in error ID and or password not recognised
frustration  - I suppose i'll have to subscribe to blackberry email for another £5 a month if it's going to be this much hassle to get into webmail
any ideas appreciated