[metapost] Problems with `pt' unit of lenght after saying `path pt'

[Rodolfo Medina]

In the same .mp file: if, in fig(1), I said: `path pt', then in fig(2) there
are problems in using pt as the usual unit of lenght.

Any possible ways to avoid that, without using two different files for fig(1)
and fig(2) *and* wanting to use `pt' to name a path?

Thanks,
Rodolfo