[xcrysden] error executing

[somayyeh sheikholeslami]

Dear users
could anybody help me to solve this error, please?
somy at somy-laptop:~$ xcrysden

+----------------------------------------------------------------+
|****************************************************************|
|*								*|
|*  XCrySDen - (X-Window) CRYstalline Structures and DENsities  *|
|*		=         ===         =              ===        *|
|*--------------------------------------------------------------*|
|*								*|
|*    Anton Kokalj (Tone.Kokalj at ijs.si)                         *|
|*    Jozef Stefan Institute, Ljubljana, Slovenia               *|
|*								*|
|*    Copyright (c) 1996--2004 by Anton Kokalj                  *|
|*                                                              *|
|****************************************************************|
+----------------------------------------------------------------+

  Version: 1.5.17

  Please report bugs to: Tone.Kokalj at ijs.si


  TERMS OF USE:
  -------------
  XCRYSDEN is released under the GNU General Public License.

  Whenever graphics generated by XCRYSDEN are used in scientific
  publications, it shall be greatly appreciated to include an explicit
  reference. The preferred form is the following:

  [ref] A. Kokalj, Comp. Mater. Sci., Vol. 28, p. 155, 2003.
        Code available from http://www.xcrysden.org/.

XCRYSDEN_TOPDIR=/home/somy/SOURCE/XCrySDen-1.5.17-bin-shared
XCRYSDEN_SCRATCH=bashrc

Running on platform: unix
Error in startup script: wrong # args: should be "set
varName ?newValue?"
    while executing
"set system(c95_crystal)    -p: not found"
    (file "/home/somy/.xcrysden/custom-definitions" line 14)
    invoked from within
"source $env(HOME)/.xcrysden/custom-definitions"
    invoked from within
"if { [file exists $env(HOME)/.xcrysden/custom-definitions] } {
	source $env(HOME)/.xcrysden/custom-definitions
    } else {
	source $system(TOPDIR)/Tc..."
    ("eval" body line 20)
    invoked from within
"eval [info body xcInit]"
    (file "/home/somy/SOURCE/XCrySDen-1.5.17-bin-shared/Tcl/xcInit.tcl"
line 530)