You are going to have to provide more details than this.
What are you trying to DO with the ID value? What is the error you are getting?
Given that you are calling a DB query I will venture a guess:
I have seen cases where you call a DB query with a value that should actually be characters, but you don't wrap it in quotes. It will work when the value is just numbers. Somehow the DB server can interpret it correctly. But as soon as you throw a character in the mix, it chokes because it doesn't interpret the sequence of characters as a number any more but as a string.
Check your query construction and verify the ID being passed is inside of quotes.