I can receive but can't send message

Hello
Slackware 10 , Qmail, vpopmail no imap are installed on my system with
outlook express all users are receive and send messages but with sqwebmail
4.0.7 I can receive message but I can't send message
my configure is below

./configure --with-authvchkpw --enable-changepass --enable-unicode=ISO8859-9
--without-gzip  --enable-imagedir=/usr/local/apache/htdocs/images
--with-cachedir --enable-mimetypes=/usr/local/apache/conf/mime.types
--enable-cgibindir=/usr/local/apache/cgi-bin/ --enable-mimecharset=ISO8859-9
--enable-hardtimeout=43200  --enable-softtimeout=3600 --enable-autopurge=1
--enable-maxpurge=3 --enable-imageurl=http://onur.uludag.edu.tr/images
--without-authpam --without-authuserdb --enable-webpass=no --without-authpwd
--without-authshadow

and in apache error_log file below

[Mon Aug  9 11:37:42 2004] [error] [client 172.16.153.17] Premature end of
script headers: /usr/local/apache/cgi-bin/sqwebmail

please help me