I did some research but didn't got a final answer.
That's what I've got about the swiss version (Pz 87)
1. Swiss variant (based on A4) built at the Federal Construction Works in Thun, Switzerland. First 35 manufactured at Krauss-Maffei in Munich; last 345 at Federal at 72 tanks/year rate with the final delivery in 1993.
Modifications include
Baird passive night periscope, Swiss machine guns and communications equipment, digital fire control computer, and improved NBC protection. It also has a slightly different turret rear and improved noise-reducing exhaust mufflers.
2. Swiss tanks were improved to the Leopard 2A5
standard in 2000/2001
3. Switzerland is
not using the wedge armour developed in Germany and used for all Leopard 2A5+ versions
4. From 2008 around 120 Pz 87 will be upgraded and designated Pz 87 WE (~A6 standard, mine protection)
5. Instead of the wedge armour the 230mm strong boxes are used which keep the well known form of the Pz 87 turret ...
A good source is here:
http://www.militaryphotos.net/forums...p/t-31407.html
and here:
http://www.kampfpanzer.de/ -- but off line at the moment...