Bug (or feature?) in eqn ?

[sarwate at uicsl.UUCP]

The man page for eqn states that "All text that is neither between delimiters
nor between .EQ and .EN is passed through untouched." However, when I run the
following through eqn,

.EQ
delim $$
.EN
.LP
$A$ \f2or $B$ or C.

it appears that eqn treats the entire line as an equation and creates the long
string \*(11 given by

             \x'0'\f2\s10A\s10\f1 \f2or \x'0'\f2\s10B\s10\f1 or C.

In the midst of all the font changes introduced by eqn, the fact
that the font was changed to italics just before the word "or" is
completely missed. After the $B$ is processed, the font is reset to what it
was just after the .LP command, i.e. roman font.  Thus, the words "or C." appear
in roman font, rather in italic font, as I expected.  Is this a bug? or is it a
feature? (We have a 4.2bsd system.)