Because by all accounts this isn't a Java/JVM issue. It's a flaw in a commonly used algorithm for handling floating point numbers. Given that php and possibly gcc use variations on the same algorithm, and have the same flaw, it's not unreasonable to think that other languages/compilers/runtimes would also be affected.
As the article "The PHP strtod() denial of service bug" (http://blog.andreas.org/display?id=9 ; linked by pilif in another comment) states, it looks like the code for the conversion is used in a few prominent libraries (e.g. Apple's libc, Android libc, GCC libio etc.). Therefore, it could've been quite possible that the mentioned code has been adopted by Microsoft, too; leppie just confirmed that everything works fine over there.
I guess because only a couple of weeks ago a similar issue has surfaced in PHP so it is not entirely unreasonable to check whether other runtimes have similar problems?
