libcap is a library for getting and setting POSIX.1e 
(formerly POSIX 6) draft 15 capabilities.

libcap v2 implements support for filesystem capabilities; however,
the kernel shipped with Slackware 12.1 does not support this.

	# grep CAPABILITIES /boot/config
	CONFIG_SECURITY_CAPABILITIES=y
	# CONFIG_SECURITY_FILE_CAPABILITIES is not set

To enable this support, recompile the kernel with this option set:

	Security options  --->
		Enable different security models
			Default Linux Capabilities
		File POSIX Capabilities (EXPERIMENTAL)

Even if you don't use this, the actual lib should still be compatible
with libcap v1 in the 12.0 repo. If, however, this happens to not actually
be the case, the SlackBuild there should still work fine on 12.1.

Additional URL pointers (besides the project homepage):

POSIX file capabilities: Parceling the power of root by Serge E. Hallyn
http://www.ibm.com/developerworks/linux/library/l-posixcap.html?ca=dgr-lnxw06LinuxPOSIX

Using Capabilities by Olaf Kirch
http://www.lst.de/~okir/blackhats/node125.html

POSIX 1e and 2c drafts:
http://wt.xpilot.org/publications/posix.1e/download.html