We define Unsigned32 as [Application 7], which was part of RFC1442 (1993),

We define Unsigned32 as [Application 7], which was part of RFC1442 (1993),
but was removed in RFC1902 (1996), where it was made equal to Gauge32.

There's no real harm in keeping it, since nothing else uses
[APPLICATION 7], but add a comment to help out any future lost soul that
might wander into this.

OK benno@