[gentoo-user] Group Calendaring with decent Outlook interaction

[Tanstaafl]

Hi all,

We use Thunderbird+Lightning+Provider for Google Calendar+Google 
Calendar here in our office, and the calendaring really is becoming more 
and more problematic for us, mostly with respect to interacting with 
Meeting Invites from external users of Outlook/Exchange.

I'm curious if anyone has any suggestions for a hosted calendaring 
solution  that works well with Thunderbird+Lightning *and* deals 
properly with meeting invites from outlook/Exchange users? This is for a 
business, so commercial/paid service is not out of the question, but I 
do prefer free if available...