[Evolution] evolution-mapi sync renders evolution unaccesible

["kingma bluewin ch" <kingma bluewin ch>]

Steps to reproduce
1) open evolution on a laptop within a windows domain, connectiing it to a mapi source
2) put the laptop to standby
3) Move the laptop to a network outside the windows domain
4) start a syncing email
5) cancel the sync

what happens: evolution becomes unresponsive with the sync window open
expected behaviour: evolution stops the attempt and becomes avaiable again.