Emails to Blackberry's/iPhone

Hi,

We have one server running SBS 2008 with Exchange 2007.

We have OWA working internally and remotely usinr https://remote.mydomain.com

All details are correct when entering onto mobile devices, iPhone through phon eitself, Blackberry's through relevant website.

These phones will not connect and collect emails.

I have compared all Exchange 2007 settings to another server which works like a dream

Any assistance, advice, pointing in the right direction would be great.

Thanks

C