except salesforce, sugarcrm, are there any free crm on php?

[blackhorse]

except salesforce, sugarcrm, are there any free crm on php?

Both sugarcrm or salesforce are heavy weight and not cheap, even they are open source.

I am looking for a light weight but still with good quality CRM system on php, and free open source.

It seems that for the ecommerce systems if there are a good commercial ones, there are always good free ones too in open source (maybe light weight).

But for CRM, for years, no free open source CRM really can match up with SugarCRM or salesforce, why?

Any suggestions?

[blackhorse]

How about vtiger? Free and lightweight. Any one has experience with all these CRMs, any advantages and disadvantages of sugarcrm vs. vtiger etc. you want to share?