how can i avoid lots of warning info when i start systemtap script??

[ch huang]

~~~~~~~~~~~~~~~~~like this

WARNING: cannot find module nfs debuginfo: No DWARF information found
WARNING: cannot find module nfs debuginfo: No DWARF information found
WARNING: cannot find module nfs debuginfo: No DWARF information found
WARNING: cannot find module nfs debuginfo: No DWARF information found
WARNING: cannot find module nfs debuginfo: No DWARF information found
WARNING: cannot find module nfs debuginfo: No DWARF information found
WARNING: cannot find module nfs debuginfo: No DWARF information found
WARNING: cannot find module nfs debuginfo: No DWARF information found
WARNING: cannot find module nfs debuginfo: No DWARF information found
WARNING: cannot find module nfs debuginfo: No DWARF information found

Sat Mar 24 05:35:08 2012 , Average:1409Kb/sec, Read:    6833Kb, Write:    211Kb

     UID      PID     PPID                       CMD   DEVICE    T        BYTES
      27    23891    23461                    mysqld    xvdc1    R      6752968
      27    23891    23461                    mysqld    xvdc1    W       216157
       0    21993    21940                     mysql    xvda1    R        44596
       0    22006    21940                     mysql    xvda1    R        44596
       0    22021    21940                     mysql    xvda1    R        44596
       0    22034    21940                     mysql    xvda1    R        44596
       0    22049    21940                     mysql    xvda1    R        44596
       0    21993    21940                        sh    xvda1    R         3620
       0    22006    21940                        sh    xvda1    R         3620
       0    22021    21940                        sh    xvda1    R         3620