Calculating dependencies                                                                                                  -
!!! All ebuilds that could satisfy "xf4vnc" have been masked.
!!! One of the following masked packages is required to complete your request:
- net-misc/xf4vnc-4.3.0.999 (masked by: missing keyword)
- net-misc/xf4vnc-4.3.0.103 (masked by: missing keyword)
- net-misc/xf4vnc-4.3.0.104 (masked by: missing keyword)

For more information, see MASKED PACKAGES section in the emerge man page or 
refer to the Gentoo Handbook.