DAM> A sample mex will be great help. Thanks.
Here it is!
-----------------------------------------------------
/////////////////////////////////////////////////////////////////////////////
//
// File: PHONE.mex
//
// Desc: Check user's VOICE and COMPUTER phone numbers
//
/////////////////////////////////////////////////////////////////////////////
#define INCL_global
#include 
#include                            // MNU_CHG_HOTKEYS
void main()
{
    int:    ch,
            loop,
            save_hot;
    string: phone,
            dataphone,
            template,
            choice,
            str_enter_ph;
    save_hot     := usr.hotkeys;                  // Save Hot Key setting
    // if the number is already 14 characters long - exit
    if (strlen(usr.phone)=14) goto chek2;
    // if the number is in the old 13 character format - convert to 14
    if (strlen(usr.phone)=13)
    {
      phone     := substr(usr.phone,1,5)+" "+substr(usr.phone,6,8);
      usr.phone := phone;
      return;
    }
    // print("\nYour VOICE phone number has not been entered or " +
    //      "was entered incorrectly\n");
    str_enter_ph := "Please enter your VOICE number:";
    template     := str_enter_ph + " (...) ...-....";
    loop         := 0;
    // Turn Hot Keys on temporarily if not already on
    if (usr.hotkeys  1)  menu_cmd(MNU_CHG_HOTKEYS,"");
    while (loop=0)
    {                                            // Start While
      do
      {                                          // Start Do While
        if (strlen(phone)=0) phone := str_enter_ph + " (";
        if (strlen(phone)=strlen(str_enter_ph)+5) phone  := phone + ") ";
        if (strlen(phone)=strlen(str_enter_ph)+10) phone := phone + "-";
        print("\r",template,"\r",phone);
        choice := "0123456789";
        if (strlen(phone)=(strlen(str_enter_ph)+2)) choice := "23456789";
        if (strlen(phone)=(strlen(str_enter_ph)+7)) choice := "23456789";
        ch := input_list(choice, CINPUT_FULLPROMPT |
              CINPUT_NOLF, "", "\r"+template+"\r"+phone, "");
        phone := phone + itostr(ch-48);
      } while (strlen(phone)strlen(str_enter_ph)+15);
      print("\r",phone,"\n\n");
      ch := input_list("yn", 0, "", "",
            "Was your phone number entered correctly");
      if (ch  89) phone := "";
      else          loop  := 1;
    }                                            // End While
    usr.phone   := substr(phone,strlen(phone)-13,14);
    
chek2:    
    // if the number is already 14 characters long - exit
    if (strlen(usr.dataphone)=14) return;
    // if the number is in the old 13 character format - convert to 14
    if (strlen(usr.dataphone)=13)
    {
      dataphone     := substr(usr.dataphone,1,5)+" 
"+substr(usr.dataphone,6,8);
      usr.dataphone := dataphone;
      return;
    }
    // print("\nYour COMPUTER phone number has not been entered or " +
    //      "was entered incorrectly\n");
    str_enter_ph := "Please enter your COMPUTER number:";
    template     := str_enter_ph + " (...) ...-....";
    loop         := 0;
    // Turn Hot Keys on temporarily if not already on
    if (usr.hotkeys  1)  menu_cmd(MNU_CHG_HOTKEYS,"");
    while (loop=0)
    {                                            // Start While
      do
      {                                          // Start Do While
        if (strlen(dataphone)=0) dataphone := str_enter_ph + " (";
        if (strlen(dataphone)=strlen(str_enter_ph)+5) dataphone  := dataphone
 
+ ") ";
        if (strlen(dataphone)=strlen(str_enter_ph)+10) dataphone := dataphone
 
+ "-";
        print("\r",template,"\r",dataphone);
        choice := "0123456789";
        if (strlen(dataphone)=(strlen(str_enter_ph)+2)) choice := "23456789";
        if (strlen(dataphone)=(strlen(str_enter_ph)+7)) choice := "23456789";
        ch := input_list(choice, CINPUT_FULLPROMPT |
              CINPUT_NOLF, "", "\r"+template+"\r"+dataphone, "");
        dataphone := dataphone + itostr(ch-48);
      } while (strlen(dataphone)strlen(str_enter_ph)+15);
      print("\r",dataphone,"\n\n");
      ch := input_list("yn", 0, "", "",
            "Was your COMPUTER number entered correctly");
      if (ch  89) dataphone := "";
      else          loop  := 1;
    }                                            // End While
    usr.dataphone   := substr(dataphone,strlen(dataphone)-13,14);
    usr.hotkeys := save_hot;                     // Reset Hot Key Setting
    print ('\n',
    "Thank you, I've updated the records to show the following:",
    '\n', "Voice phone # = ",usr.phone, '\n',
    "Data phone #  = ",usr.dataphone, '\n');
    sleep (15);
    return;
    }
------------------------------------------------------------------
I don't understand a lick of it, but someone gave it to me and it works.  It 
will ask new users for both, and it will ask existing users for the missing 
data number.
Robby
--- Maximus 3.01
---------------