[R] Titles in plots generated within tapply

[Dennis Malandro]

How would one go about putting titles in each of several plots
that are generated from within a call to tapply?  For example I'd
like the following two barplots to have titles 'Group 1' and
'Group 2', where '1' and '2' come from the levels of 'group'.

group <- gl(2, 10)
result <- sample(c('A', 'B'), size=length(group), replace=TRUE)
windows(7, 4)
par(mfrow = c(1, 2))
tapply(result, group,
       function(x) barplot(table(x), xlab = 'Result'))


I found something close to what I'm looking for here
http://tolstoy.newcastle.edu.au/R/help/04/09/3219.html.  So I
tried

mapply(function(x) barplot(table(x), xlab = 'Result'),
  split(result, group), main = levels(group))

Error in function (x)  : unused argument(s) (main ...)

(I expected to get titles of '1' and '2'.  Not exactly what I
asked for in the question, but it would have been progress.)

Much obliged,
Dennis