xdg-open 'http://www.muenster.de' does not work, only without '

[Schreiber]

kubuntu 12.04
The man for xdg-open says, that I habe to use 'url', but that only makes a mistake-message,
man: xdg-open 'http://www.freedesktop.org/'
When I do this:
xdg-open http://www.muenster.de all is ok.
The problem is that some programs , especially with java (calibre, zettelkasten) can no longer open url. I have the suspicion that this was grounded in changes of xdg-open.

Sorry for my bad english. If You need more information, please give me a message.

Description: Ubuntu 12.04.3 LTS
Release: 12.04

xdg-utils:
  Installiert: 1.1.0~rc1-2ubuntu6
  Kandidat: 1.1.0~rc1-2ubuntu6
  Versionstabelle:
 *** 1.1.0~rc1-2ubuntu6 0
        500 http://de.archive.ubuntu.com/ubuntu/ precise/main i386 Packages
        100 /var/lib/dpkg/status

[Schreiber (schreiber07)]

Sorry, I made a mistake with the url. I can open the url 'http://www:muenster.de'. But indeed the java-programs calibre and zettelkasten can no longer open url with xdg-open (java version "1.7.0_45"). I don't know which update caused this.
Sorry.