Comment 18 for bug 226119

There is definitely a conflict with your installed libraries.

run

  ldconfig -v

look for all lines containing

  libQt*.so.4

There are probably at least two different versions of libraries. I had the same error, in my case it was not nessus but the libraries shipped with the software for Aladdins eToken... (installed version was 4.4.0 but Aladdin shipped some libs in Version 4.3.4)

remove the entry corresponding to that older version from ld.so.conf or ld.so.conf.d, run ldconfig and cross your fingers :)

Hope that helps

Chris