Nokia N97 voicemail number

[Glocko]

I've just swapped phones to an N97 on O2 (UK)
When I try to retrieve voicemails it dials my own mobile number! (I may have input this when first trying to get voicemail and it now defaults.
Is there a central voicemail number it should be dialling? If it is password protected can I restore to defauilt?
Thanks chaps

[spitfire-ian]

O2's voicemail number is 901