Application Delimiter Issue

I am very confused by this error. I am using Asterisk 1.8.3. The system was working perfect with comma sign as application delimiter in the GoTo application. Out of no where, after reloading dialplan, I started getting the error:
The application delimiter is now the pipe, not the comma. Did you forget to convert your dialplan?

I go to my dialplan, change the comma to pipe, reload the dialplan and all is well. After a few months, I start getting the error again, this time its the opposite

The application delimiter is now the comma, not the pipe. Did you forget to convert your dialplan?

I have not made any major configurational changes or version upgrades. Why does the delimiter keeps changing randomly?? :confused:

Did anyone face the same issue?

Ahsan