port tree fetch errors

[Tofik Suleymanov]

My ports-supfile is:

*default host=cvsup.nl.FreeBSD.org
*default base=/var/db
*default prefix=/usr
*default release=cvs tag=.
*default delete use-rel-suffix
*default compress
ports-all

i do:

cvsup -g -z -L 2 /etc/ports-supfile 

and get this:

Updating collection ports-all/cvs
Cannot calculate checksum for "/usr/ports/devel/boost/pkg-plist": 
Input/output error
Cannot calculate checksum for 
"/usr/ports/devel/clint/files/patch-python.h": Input/output error
Cannot calculate checksum for 
"/usr/ports/devel/crossgo32-djgpp2/pkg-plist": Input/output error
 Checkout ports/devel/Makefile
Cannot calculate checksum for "/usr/ports/devel/elib/files/patch-aa": 
Input/output error

Need to mention that after cvsup ends i cannot compile php4 and get this 
errors:
"Makefile", line 125: warning: " -q MPM_NAME" returned non-zero status

Something happened to ports tree ?
I've also tried different cvsup servers also, but had no success.