jpgraph not working after upgrade to 1.0.0.3a

[Alice]

I had a working version of mantis 0.19.2 with a working jpgraph on the summary page.

After making an upgrade to 10.0.a3 jpgrapgh stopped working.
I can only see red crosses instead of pictures.
I changed nothing only upgrade .
may you help me.

Thanks in advance

Alice