nroff bug query

[Eric Gisin]

In term(5), the description of bdon (turn on boldface) says
`nroff assumes that bdon is reset by twnl (newline)'.
Therefore nroff should generate bdon for every line requiring
boldface, but it doesn't.
For example, in `nroff -Txerox -man /usr/man/man5/utmp.5'
all three lines beginning at `SYNOPSIS' should be bold,
but only the first is printed bold.
Does anyone have a fix to make nroff match the documentation?
I'm using V7/4BSD troff with tabxerox from 4.2 (I think).