The BBC has suspended the BlackBerry PDA service used by more than 300 senior executives, including Director General Mark Thompson.

A BBC spokeswoman told vnunet.com: "Last week we noticed a fault in that some users were getting fragments of other people's email in their own email. So we suspended the service and it will remain suspended until it is fixed."

Executives are having to revert to PC-based email and phones rather than use the BlackBerry devices which allow them to make phone calls as well as receive texts and emails.

The BBC's IT services supplier, Siemens, is taking responsibility for solving the problem.

BlackBerry manufacturer Research In Motion said in a statement: "RIM has developed and tested a fix for an obscure bug identified in a specific service pack release for BlackBerry Enterprise Server.

"The bug was isolated to version 4.02 and does not exist in version 4.03 or other earlier versions. RIM is aware of a single reported incident of the bug, and responded promptly with a fix."

The bug related to a "rare conjunction" of circumstances "whereby v4.02 failed to properly compensate for an unusual memory allocation error generated by a company's mail server and consequently appended a partial message to another email.

"Neither the original message or the appended partial message were ever exposed outside the company's firewall and the bug did not generate any external risk. Customers using v4.02 may obtain this fix from RIM or install v4.03."