new fixed issues:
APS-28626 Query string parameters are missed for entry points with GET method
Hotfix can be downloaded here.
Use pa_updates_installer (https://kb.cloudblue.com//111323) to install this hotfix. Also this hotfix will be installed automatically during upgrade to OA 5.5.9 via pa_updates_installer. To install hotfix manually obtain its installation package from the link above and follow instructions found in file UPDATE.txt of distributive.