Tracking system needed

Dear Lazyweb,

a lot of my customers have workflows that involve different people. Some of them have checklists, but this is a lot of paper work, it’s not searchable, not reliable and it’s just so 1987. To make these processes more transparent and traceable I am looking for a issue tracker/ticketing system/CRM.

A typical workflow looks like this:

1. Customer orders goods, services, whatever. There are several ways to order: Via website, telephone, fax or reseller.
2. Employee receives order. If there are open questions, employee sorts them out with customer or reseller.
3. Employee confirms the order and sends out a bill.
4. Customer/reseller makes a depsit.
5. Employee confirms deposit and sends out another mail with more info on product or service.
6. Customer/reseller pays the outstanding sum of money.
7. The deal takes place.

The thing I’m looking for should be lightweight because there already are dedicated systems for booking, accounting and so on that we cannot replace, but there is nothing that brings all these systems together. I only what to track the process and to do this, I’d like to have the following features:

• Web interface: I don’t want to install additional client software.
• Custom statuses: If possible, employees should be able to define them via web interfacel, but that’s not high priority
• Custom Workflows: If possible, the system should be able to define custom actions such as sending out an email when state X is reached
• Custom fields: I’d like to be able to add different fields to the tickes,
• Attachments: I’d like to attach files to tickets.
• Localization: If possible, because “… Es ist Deutschland hier.” 😉

So far I have looked at Mantis, OTRS, Redmine (all nice and powerful bug trackers, but not really what I’m looking for need and lack some features need), Drupal with plugins (I haven’t found the right plugin and I don’t want to carry the cruft of a complete CMS when I just need a tracker) and the well known trac (currently my favorite although it was definitely designed for other purposes).

Dear Lazyweb, do you know any other systems that offer what I’m looking for?