sprintf doesn't care of escape characters

Hi.

I am having trouble with something that should be simple. I am unable
to get sprintf using escape sequences:

sprintf("a\nb")

[1] "a\nb"

sprintf("a\"bc\"d")

[1] "a\"bc\"d"

But it seems to need them any way:

sprintf("a\"bc"d")

Error: unexpected symbol in "sprintf("a\"bc"d"

Any suggestion on how to solve this issue?

My R system:

version

_
platform       x86_64-suse-linux-gnu
arch           x86_64
os             linux-gnu
system         x86_64, linux-gnu
status
major          2
minor          15.0
year           2012
month          03
day            30
svn rev        58871
language       R
version.string R version 2.15.0 (2012-03-30)

Thanks.