Installed roundcube last week and a newbie to this software.
most everything works, the biggest problem is below:
when ever I send an email receive above error message in /var/log/http/errrorlog. the email is received and sent successfully by sendmail. 
sometimes also see the following message...
[Tue Nov 05 12:05:57 2013] [error] [client 10.2.2.1] Invalid method in request \x16\x03
( 10.2.2.1 is the internal firewall address ) 
Roundcube Webmail 0.9.5
centos 6.4
sendmail
filesystem_attachments   1.0   GNU GPLv2   
plugin_maager   21.1.19   All Rights reserved   Download
qtip   1.2   GNU GPLv3+   
show_aditional_headers   2.0   GNU GPLv2   
userinfo   1.0   GNU GPLv3+   
thoughts ?
jim mc....