The PIC18F2420/2520/4420/4520 Rev. A1 parts you
have received conform functionally to the Device Data
Sheet (DS39631), except for the anomalies described
below. Any Data Sheet Clarification issues related to
the PIC18F2420/2520/4420/4520 will be reported in a
separate Data Sheet errata. Please check the
Microchip web site for any existing issues.