Things You'll Need
Instructions
Create an account with an SIP provider such as voipbuster.com or freecall.com. Registration is free, but most SIP providers charge for credits to make calls.
Download SvSIP from its website at svsip.free.fr. Extract the downloaded files and copy and paste them to the root of your micro SD card.
Open the folder named "svsip" and locate the text document titled "config." Open it. Replace each "XXXX" with the parameters designated on the svsip website, which are located in the "SIP Configuration" link under "Instruction." Save the file.
Open "Network Connections" on your PC's control panel. Right-click your Wi-Fi connection and click "Properties." Click on the "Advanced" tab, then click the button that reads "Settings." Click the "Exceptions" tab to open ports 5060 and 4000 to 4007 on your firewall. These ports must be open for SvSIP to work on your DS.
Insert the micro SD card into the DS flash card. Insert the DS flash card into the DS. Open "wifi-config.nds" and select "Connect to an AP." If you have your DS hooked up to your Wi-Fi connection, then select "Use Nintendo WFC Data" to simply transfer over the information. Otherwise, select "Search for an AP" or "Manual Configure" to set up your connection. Select "Save configuration" when you are done.
Open "SVSIP.nds" and wait for the number pad to appear on the touch screen. Dial 1, the area code and the phone number and wait for the call to be answered.