Merkaartor plugin directory

Due to a system upgrade, I reinstalled Markaartor 0.18.1. Now the plugins (e.g. Bing) won’t show up in the menu. The plugins are located in the /usr/local/lib/merkaartor/plugins/background/ directory, but Merkaartor does not see them for some reason. I did not find a configuration entry to define the location of the plugin directory. Anybody know how to tell merkaartor where to look for them?

Kdelibs were missing. I wonder why merkaartor compiled without complaining. Reinstalling kdelibs and merkaartor solved the problem.