Yealink phones not completing transfer?

[randomness]

New install, latest versions all round. When a call is transferred via a Yealink T26 phone, although the call transfers ok, regardless of whether 'Transfer' is pressed a second time to complete, or the phone is hung up; call still shows as active (via myphone etc) on both the originators extension and the new extension. Calls can be made from the 'old' extension, but no new ones until the third party hangs up.

Known problem? Probably just a setting I guess?

 

[countrycomp]

What firmware are you using on the Yealinks? We started to see this behaviour with x.61.x.x firmware and have reverted back to x.60.x.x today and have not seen the problem since.