sendmail attachment problem

Hello,

i am sending email with following command.
The problem is the attachment is displayed as inline text instead of a file attached to email. What should i do?
I don't have chance to install new binaries to the server (SunOS)

( \
echo From: Sender[test@test.com] ; \
echo Subject: Testing ; \
echo To: recipient@test.com ; \
echo message ; \
uuencode -m attach.file1 attachname1 ; \
) | sendmail recipient@test.com

Attachments are actually not a "real thing" in smtp, it's just what your mail reader makes of it.
Try using mime encoding (mpack) instead of uuencode to give maximum compatibility with most readers out there.