(using MDV2007.0, bluetooth works, phone gprs works)

I'm trying to set up my mobile as a modem (bluetooth & gprs). Using KPPP, I've configured the modem and account, and got to the point where the phone asks if it should bond to "BlueZ (0)" after I click on "connect" in the KPPP interface. On saying "yes" to this, it asks for the passkey, but then keeps returning "Invalid PIN".

My /etc/bluetooth/hcid.conf looks like this (default after bluez installation from MDV2007.0 package archive, though I've changed the passskey):

Code:
options {
	autoinit yes;
	security auto;
	pairing multi;
	passkey "1234";
}

device {
	name "BlueZ (%d)";
	class 0x3e0100;
	iscan enable; pscan enable;
	lm accept;
	lp rswitch,hold,sniff,park;
}
At some point I removed the 'passkey "1234";' line and put 'pin_helper /etc/bluetooth/bluepin;', with the bluepin file containing:
!/sh echo "PIN:1234"
but this did not seem to solve anything.

My /etc/bluetooth/rfcomm.conf looks like this:

Code:
rfcomm0 {
	bind yes;
	device 00:1a:db:bb:78:6b;
	channel 1;
	comment "Motorola Phone";
}
(The "channel 1" I got from running 'sdptool browse 00:1a:db:bb:78:6b')

The MDV2007.0 Errata contains the following, and I include this because I don't know if it's relevant to my issue:

See also Image:bug_small.png Bug #24359 and update advisory MDKA-2007:008. Mandriva Linux 2007 includes the latest version (3.2) of bluez, the Linux Bluetooth support layer. This changed caused problems with the system for running an application to ask for PIN codes when pairing or authenticating with another bluetooth device, rendering this operation difficult. An updated bluez-utils package, bluez-utils-3.4-4.1mdv2007.0, was released through the official update channels on January 11th, 2007 that resolves this issue by ensuring the PIN code will be requested when necessary. Use MandrivaUpdate to fetch and install this update. You may still experience your system not being discoverable by other bluetooth devices: refer to Issues with Bluetooth discoverability, below, for a workaround for this problem.
Any help would be very much appreciated.