problem of install the NIOS2eds

Hello,

i have a problem of install the NIOS2-ide under ubuntu 8.10

after install ,when i would launch nios2-ide the message appear:

the configured quartus II version[quartus-unkown] does not match the current NIOS II EDS version[9.1].

Ensure that the Quartus_ROOTDIR and SOPC_KIT_NIOS2 environement variables are set correctly.