How to increase CNFS buffer length ?

Hello,

I've installed for test inn-2.3.3 on a SUN server running SunOS 5.9
and I've defined CNFS buffers via mknod on raw partitions in cycbuff.conf :

cycbuff:ONE:/cycbuff/c0t2d0s4:2000000
cycbuff:TWO:/cycbuff/c0t2d0s5:2000000
cycbuff:THREE:/cycbuff/c0t2d0s6:2000000
cycbuff:FOUR:/cycbuff/c0t2d0s7:2000000

metacycbuff:BIGAREA:ONE,TWO,THREE

All is running OK but now if I want to increase the size
of the last CNFS buffer FOUR (using format utility and modifying in 
cycbuff.conf : cycbuff:FOUR:/cycbuff/c0t2d0s7:4000000)


May 13 11:41:00 newsbis.univ-rennes1.fr innd: [ID 814968 news.error] CNFS-sm: 
Mismatch: read 0xdc6c0000 length for cycbuff /cycbuff/c0t2d0s7
May 13 11:41:00 newsbis.univ-rennes1.fr innd: [ID 371779 news.error] SM 
storage method 'cnfs' failed initialization
May 13 11:41:00 newsbis.univ-rennes1.fr innd: [ID 292155 news.error] SM one or 
more storage methods failed initialization
May 13 11:41:00 newsbis.univ-rennes1.fr innd: [ID 892631 news.crit] SERVER 
cant initialize the storage subsystem one or more storage me
thods failed initialization

In fact the old size 2GB of cycbuff FOUR is always memorized :

% cnfsheadconf -c  FOUR
 Buffer FOUR, len: 1953.12 Mbytes, used: 292.21 Mbytes (15.0%)   1 cycles
 Meta , order: 0, current: TRUE
 Newest: 2003-05-20  9:55:01,    0 days,  0:21:28 ago

and I can't modify its length via the -w option of cnfsheadconf

So how I could erase all reference of the old length of this CNFS buffer
to reinitialize a new CNFS buffer using the same raw partition name ?

                                                Thanks  Jacques