Is your problem already fixed (for this is an older node)?
I've had the same problem, but only when I used 'rxvt', everything ok when I used a 'xterm'. I originally thought this was a perl problem because I encountered it first when using 'perl -d'. In the end (after a lot of debugging and searching) I took al look at the 'stty -a' output and guess what I found:

'rxvt'

...
cchars: discard = ^O; dsusp = ^Y; eof = ^D; eol = <undef>;
        eol2 = <undef>; erase = ^?; erase2 = (; intr = ^C; kill = ^U;
        lnext = ^V; min = 1; quit = ^\; reprint = ^R; start = ^Q;
        status = ^G; stop = ^S; susp = ^Z; time = 0; werase = ^W;
...
[download]

'xterm'

...
cchars: discard = ^O; dsusp = ^Y; eof = ^D; eol = <undef>;
        eol2 = <undef>; erase = ^H; erase2 = ^H; intr = ^C; kill = ^U;
        lnext = ^V; min = 1; quit = ^\; reprint = ^R; start = ^Q;
        status = ^T; stop = ^S; susp = ^Z; time = 0; werase = ^W;
...
[download]

Setting erase2 ('stty erase2 ^?') resolved my problem in 'rxvt'.
Hope this helps.