The Pirelli Discus (TM) DualPhone DP-L10 is a nice WLAN-phone with mixed GSM/VoIP-capabilities.

It's branded by some ISPs and is also known as:

• Acor Twintel

Quick Review (after one day playing with it):

• firmware is not available by Pirelli, alternative firmware sources are Sipgate and Arcor (with branding)
• WLAN with WPA2-PSK works great (password length is limited), EAP did not work but could have been my setup
• hidden functions (###800# engineering mode, ###810# Remove User Data!, ###520# Show Version)
• DTMF is send as audio? (did not check further:echo test cancel with # does not work, some external Voicebox does not work, but DISA works)
• only one SIP-account supported (but there exists reports with multiple accounts in other firmwares)
• modern design, acceptable quality
• integrated browser for WAP and Web (limited use, only simple pages)
• interoperability with asterisk was no problem
• supports multiple simultanous VoIP-calls (no conferencing)
• configuration via phone menu no browser (quite a job entering the WPA2 key)
• Windows based update software

After using it for a couple of days here are my issues:

• the firmwares are more or less the same, Arcor has the latest version, but DTMF does not work for me (seems to be inband)
• I had some limited luck setting up my own provisioning: Firmware update via Web is much easier if you got no Windows box :), I was also able to change some settings via my own provisioning file that I found in the image (enable some more codecs) but I wasn't able to enable DTMF via RTP (what worked in an other firmware)
• I bounced into an ugly bug that made me almost crazy: I noticed, that all incoming calls were silent (in/out) when picked up, outgoing were just fine. What looked like some NAT/RTP related issue was some kind of bug that was caused by some headset-logik. When I wasn't using the phone it was in the charger where I couldn't keep the headset plugged in. When somebody called me, I picked it up and answered - no sound. When I plugged in the headset it worked. I "solved" the problem with a factory reset....
• I didn't test the GSM, so no results for that part
• I've seen some tool that splits the firmware into multiple files from where you can start messing with it, but I was too afraid bricking my device, and an online image converter
• If you register to asterisk, set "qualify=no" to increase standby time on battery

Where to buy

• Belgium - NOVACOM Shop Delivery all over Europe. Very competitive prices.
• Europe - MyPhoneCall Europe's largest distributor of VoIP products. (payment in GBP or EUR)
• Europe - VoIPon
• Netherlands - Voipshop
• Ukraine & Europe - Wildix in Ukraine