TEL FILE EXTENSION

I have the SimMax application installed on my PC to read/edit sims of mobile phones.In the option to "open file", it is only permitting files with the ".tel" extension.On further investigation in %program files%sim maxtel folder I found more files with the ".tel" extension.My goal was to copy an address book from a PC to the mobile phone book using the gsm sim as intermediary. The sim can store only 250 names, whereas the mobile phone books can store 500 or more, so you have to copy 250 numbers at a time on to the sim which is in the simholder which itself is plugged into PC USB port.Once the 250 names are copied to the sim, the sim is removed, fixed in mobile and the 250 addresses are copied to phone book. This process is repeated until all the PCs address book is completely copied to the mobile phone book.I am unable, in the very first instance to copy names from address book of pc, which are exported originally as .xls or .csv files and the blessed sim max software is only allowing .tel files!If you can give alternate solution please advise. I was searching for any application that could convert .csv files to .tel