I have modified the algebra filter so that it can display the following greek letters :
alpha beta gamma zeta theta iota kappa lambda mu nu xi pi rho sigma tau phi chi psi omega
the following greek letters cannot be display :
delta (unknown reason : just display as "delta"), epsilon (include the substring psi), eta (substring of other greek letter), upsilon (include the substring psi).
Oh, I want to upload modified files to the server but it always display "an error happen when uploading to the server"
