RT Issues: Cannot write to '/opt/rt3/var/log/rt.log':

Hi

I got this error:
error: Cannot write to ‘/opt/rt3/var/log/rt.log’: at
/opt/pgm/perl/5.10.0/lib/site_perl/5.10.0/Log/Dispatch/File.pm line 134.
context:

130:

}

131:

else

132:

{

133:

$fh = $self->{fh};

134:

print $fh $p{message}

135:

or die “Cannot write to ‘$self->{filename}’: $!”;

136:

}

137:

}

138:

code stack:
/opt/pgm/perl/5.10.0/lib/site_perl/5.10.0/Log/Dispatch/File.pm:134
/opt/pgm/perl/5.10.0/lib/site_perl/5.10.0/Log/Dispatch/Output.pm:39
/opt/pgm/perl/5.10.0/lib/site_perl/5.10.0/Log/Dispatch.pm:147
/opt/pgm/perl/5.10.0/lib/site_perl/5.10.0/Log/Dispatch.pm:95
/opt/pgm/perl/5.10.0/lib/site_perl/5.10.0/Log/Dispatch.pm:70
/opt/pgm/perl/5.10.0/lib/site_perl/5.10.0/Log/Dispatch.pm:22
/opt/rt3/lib/RT/I18N.pm:414

The permission on the file rt.log is set to 777.

Can someone help?

Thank You
Yen-Nhi