Thank you very much.
I have another question :
It seems that the result from MIME::Base64 and Digest::MD5=md5_base64 are different.
DIGEST=$(perl -MDigest::MD5=md5_base64 -e 'print md5_base64("username");')
print $DIGEST
FMSwa4JOxZMjk2JRf1OLKQ
DIGEST=$(perl -MMIME::Base64 -e 'print encode_base64("username");')
print $DIGEST
dXNlcm5hbWU=
Any comment ?