WARNING: got empty schedule from planner

Does everyone know why I receive this error during a dump?

START driver date 20060920
DISK planner ascm01 /sqlbackup
DISK planner ascm01 /P4ROOT
DISK planner ascm01 /asp
START planner date 20060920
START taper datestamp 20060920 label Daily19 tape 0
FAIL planner ascm01 /asp 20060920 0 [Estimate timeout from ascm01]
FAIL planner ascm01 /P4ROOT 20060920 0 [Estimate timeout from ascm01]
FAIL planner ascm01 /sqlbackup 20060920 0 [Estimate timeout from ascm01]
FINISH planner date 20060920
WARNING driver WARNING: got empty schedule from planner
STATS driver startup time 5402.179
INFO taper tape Daily19 kb 0 fm 0 [OK]
FINISH driver date 20060920 time 5404.178

These dumps were to tape Daily19.
The next tape Amanda expects to use is: Daily04.

FAILURE AND STRANGE DUMP SUMMARY:
ascm01     /asp lev 0 FAILED [Estimate timeout from ascm01]
ascm01     /P4ROOT lev 0 FAILED [Estimate timeout from ascm01]
ascm01     /sqlbackup lev 0 FAILED [Estimate timeout from ascm01]

STATISTICS:
                          Total       Full      Daily
                        --------   --------   --------
Estimate Time (hrs:min)    1:30
Run Time (hrs:min)         1:30
Dump Time (hrs:min)        0:00       0:00       0:00
Output Size (meg)           0.0        0.0        0.0
Original Size (meg)         0.0        0.0        0.0
Avg Compressed Size (%)     --         --         --
Filesystems Dumped            0          0          0
Avg Dump Rate (k/s)         --         --         --

Tape Time (hrs:min)        0:00       0:00       0:00
Tape Size (meg)             0.0        0.0        0.0
Tape Used (%)               0.0        0.0        0.0
Filesystems Taped             0          0          0
Avg Tp Write Rate (k/s)     --         --         --

USAGE BY TAPE:
Label Time Size % Nb
Daily19 0:00 0.0 0.0 0

NOTES:
driver: WARNING: got empty schedule from planner
taper: tape Daily19 kb 0 fm 0 [OK]

DUMP SUMMARY:
                                     DUMPER STATS            TAPER STATS
HOSTNAME     DISK        L ORIG-KB OUT-KB COMP% MMM:SS KB/s MMM:SS KB/s
-------------------------- --------------------------------- ------------
ascm01       /P4ROOT     0 FAILED ---------------------------------------
ascm01       /asp        0 FAILED ---------------------------------------
ascm01       /sqlbackup 0 FAILED ---------------------------------------

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