Jason is right that it is a SQL limitation on the int length, and that a text field would probably be your best bet, which would require javascript validation on the field to only allow numbers.
Note that by using a text field you will lose any sorting or filtering ability in advanced find/views.
Here is some sample JavaScript for validating a text field for numbers in CRM (note this is using the Account Number field as an example).
Add the following function calls/event handlers to your form (to the account form in this case):
OnLoad: captureAccountNumber
Account Number OnChange: validateAccountNumber
//remember the previous value for rollback
var _accountNumber = null;
function captureAccountNumber() {
_accountNumber = Xrm.Page.getAttribute("accountnumber").getValue();
}
//make sure the account number is actually a number
function validateAccountNumber() {
var accountNumberField = Xrm.Page.getAttribute("accountnumber")
var accountNumber = accountNumberField.getValue();
if(!isNaN(parseFloat(accountNumber)) && isFinite(accountNumber)) //<--can use any number validation here
{
//it's a number, set the new 'previous value'
captureAccountNumber();
}
else {
//it's not a number, reset previous value and set focus to field
alert("You must enter a valid number.");
accountNumberField.setValue(_accountNumber);
Xrm.Page.getControl("accountnumber").setFocus();
}
}
Hope that helps
Paul
