problems with plot.formula

With the recent changes in R 1.9.x, it is now impossible to properly call
plot on a formula() where the formula is provided via a named first
argument.  On today's R-1.9.1-alpha:

x <- 1:10
y <- rnorm(x,0.25)

plot(x~y)

plot(x=x~y)

Error in terms.formula(formula, data = data) : 
	argument is not a valid model

plot(formula=x~y)

Error in plot(formula = x ~ y) : Argument "x" is missing, with no default

This occurs because plot.formula is no longer directly callable, 

and the
first argument to plot.formula() is 'formula' while the first argument to
plot() is 'x'.   Consequently one cannot properly pass a named first
argument since it will either fail for plot() or for plot.formula().  [I
suspect this is one reason why R CMD check complains about S3 methods that
don't match the call of the base method.]

This is much of a problem in interactive use, but it does cause problems in
functions, like my gregmisc::overplot(), which use the standard idiom

    m <- match.call()
    m[[1]] <- as.name('plot')
    eval(m, parent.frame() )