kdepim-4.4 (kmail1) in Gentoo - unsupported, dying, dead

Bitrot is accumulating, and while we've tried to keep kdpim-4.4 running in Gentoo as long as possible, the time is slowly coming to say goodbye. In effect this is triggered by annoying problems like these:

• kleopatra-4.4 segfaults immediately on start
• kmail-4.4 does not respect "Sent mail" folder of identity 
• session restore always complains that another kontact-4.4 instance is running
• on each login, a dialog box about (unfounded) problems with gnupg pops up

There are probably many more such bugs around, where incompatibilities between kdepim-4.4 and kdepimlibs of more recent releases occur or other software updates have led to problems. Slowly it's getting painful, and definitely more painful than running a recent kdepim-4.10 (which has in my opinion improved quite a lot over the last major releases).
Please be prepared for the following steps:

• end of april 2013, all kdepim-4.4 packages in the Gentoo portage tree will be package.masked 
• end of may 2013, all kdepim-4.4 packages in the Gentoo portage tree will be removed
• afterwards, we will finally be able to simplify the eclasses a lot by removing the special handling

We still have the kdepim-4.7 upgrade guide around, and it also applies to the upgrade from kdepim-4.4 to any later version. Feel free to improve it or suggest improvements.

R.I.P. kmail1.