Plugin in repository doesn't update version number

Hello, I’m not sure if this is the right place to ask. If not, please point me to the right direction.

My problem is, that I submitted a plugin update to the wordpress repository. I did everything like the documentation says to do it. I copied the trunk to tags and updated the stable tag in the readme.txt to 1.1.
To some extend it works fine. The actual installation file is now called myplugin.1.1.zip but neither in the ww.wp.xz.cn directory nor in the wordpress plugin installer it shows up as 1.1. Also there is no notification that a newer version is available.
Am I missing something? Shouldn’t the plugin repo update the version number according to the stable tag in the readme file?