Comment 50 for bug 228067

I propose a different solution to upgrade to lyx 1.5.5 that may be easier and works very well:

add the debian sid software source.
in kubuntu adept -> manage repositories -> "third party software" -> add
deb http://ftp.de.debian.org/debian sid main

then many programs become updatable, hold on! do not update!
choose lyx and request it to be upgraded
in the "preview changes" you will see that some other three of four programs will also be upgraded due to dependencies
"apply changes"

then go back to the adept -> manage repositories -> "third party software"
and remove the cross from debian 'sid' (unstable) officially supported (you may also remove it altogether if you wish but is not necessary)

fetch updates return the usual list as you had before this procedure.

However, you now have lyx 1.5.5 installed properly with the required dependencies. When these programs become superseeded by a newer version in the usual channels, they will continue to be upgraded thus keeping the adept management tidy.