An interesting update to an earlier post (Bluetooth bites Altea owner, 18 July) can be found in IT Week’s letters blog. According to Crown Mobile Communications, quite a few Bluetooth-capable smartphones and PDAs are set up so that they cannot be made to work with in-car Bluetooth systems - the kind that meld an external phone with in-car systems such as buttons on the wheel and integrated dashboard displays.

The problem is that the I-Mate’s manufacturer, HTC – which also makes O2’s XDA and similar handsets for other networks – has only enabled its Bluetooth software to work with a headset. It will never work with any car kit.

The only conceivable reason for crippling a phone's Bluetooth subsystem in this way would be to minimise the security risks of snooping attacks. Even if this is the reason, it seems a little short-sighted on the part of HTC.