Opening tabs in Iceape from KMail

[AG <computing.account@googlemail.com>]

KMail is set up to load links in the Iceape browser, where each link is 
opened in a new tab within the same window.  However, since the latest 
update, new links keep opening new windows not new tabs.  I have 
selected the option in Iceape to ensure this happens, but to no effect.  
The option checked in Iceape is Edit/ Preferences/ Browser/ Tabbed 
Browsing/ Links from other applications => "A new tab in the current 
window", but this doesn't seem to influence the actual behaviour.

Is there something I am missing?

Thanks

AG