An updated zlib package that fixes two bugs is now available for Red Hat Enterprise Linux 5.

Zlib is a general-purpose lossless data compression library that is used by many different programs.

This update fixes the following bugs:

* When used to combine two Adler-32 checksums, the adler32_combine() function could occasionally produce an incorrect result. With this update, an upstream patch has been applied to fix the underlying algorithm, and the adler32_combine() function no longer returns incorrect checksums. (BZ#622779)

* Previous versions of the zlib package installed shared libraries to the /usr/lib directory (on 64-bit systems, also in /usr/lib64). Consequent to this, when the /usr directory was on a separate partition, certain applications may have been unable to start before this partition was mounted. This update changes the installation target for these libraries to /lib (and /lib64 on 64-bit systems) to ensure that these libraries are available before /usr is mounted. For compatibility reasons, the /usr/lib directory (on 64-bit systems, also /usr/lib64) now contains symbolic links to these libraries. (BZ#678352)

All users are advised to upgrade to this updated package, which fixes these bugs.