Is it possible to add support of 64-bit integers (signed and unsigned) and 32-bit unsigned integers to PHP?

I use MySQL with BIGINT UNSIGNED fields and it's impossible to read such values from database (I can read them, but can't operate with them). I can't just convert returned string to integers because size of integers in PHP is limmited to 32-bit, and last bit is used for sign. I can write my own functions to work with 64-bit unsigned integers but it should do PHP itself.

Another problem is 32-bit integers. They always are signed integers and it is also hard to work with INT UNSDIGNED fields in database.