Just days after a security researcher blasted its Java patching system, Sun Microsystems has issued a critical update to the consumer version of its Java software.

The Java Platform Standard Edition (SE) Version 6, Update 2 release was made available on Sun's Java.com Web site Friday and is being pushed out to Java users who use the software's automatic update system, said Jacki Decoster, a Sun spokeswoman.

Sun supports four different versions of its Java SE software for desktop computers, and the company had already patched the other versions before releasing the Version 6, Update 2 release, which is the latest version of the product for consumer users.

That raised a red flag with security vendor eEye Digital Security, which said that the staggered release schedule gives criminals a chance to reverse-engineer the Java bug by looking at the patches that have been made public. Sun says that it likes this schedule because it gives developers extra time to find bugs in the product before it lands on consumers' desktops.

eEye discovered the bug back in January. It is a critical flaw in the Java Network Launching Protocol, which is used to run Java programs over the Web. Hackers could exploit this flaw by setting up a malicious Web site that could install unauthorized software on any Java-enabled PC that visited it, according to eEye.

Java users have another reason to be up to date on their patches. On Friday, the SANS Internet Storm center issued a warning about two critical flaws in the way Java processes bitmap and JPEG images.

However, those flaws were not new. They were patched in the previous Java 6, Update 1 release, which was made available in March.

These image-rendering flaws, which were discovered by Google researcher Chris Evans, have been known publicly since January 2007, and were only identified in the Java SE desktop products. Although SANS questioned whether the flaws will affect mobile phones and PDAs, they do not effect the Java Platform Micro Edition software commonly used for such devices, Decoster said.

In late June, Sun patched the bugs in Java SE Version 1.4, the last of the desktop products to receive this particular update. The 1.4 fix may have prompted the SANS alert, Decoster said.