Issue in display graph report

Hi again

I have an issue on the Report page. When I choose a report with graph, the graph is correctly generated on the server but not corretly display on the report page.

My installation is as follow:
- projeqtor root path in /myrep/projeqtor/...
- report files in /myrep/projeqtor/files/report/.. all png are ok in this folder
my apache instance is for /myrep/projeqtor --> url like http://server/projeqtor/

So when I display a report with graph, graph is correctly generated in /myrep/projeqtor/files/report/ but link in html is <img=/myrep/projeqtor/files/report/sdqsd.png...>. In my case, it should be /projeqtor/files/report/dsds.png

I try to change global configuration to set temporary report folder as ./files/report/ but it doesn't work( doesn't save the change)
Hope it's clear ...

Have a nice day