diff --git a/testsuite/example/siteconfig.tcl-1 b/testsuite/example/siteconfig.tcl-1
index 3c13f5b1..c660f24a 100644
--- a/testsuite/example/siteconfig.tcl-1
+++ b/testsuite/example/siteconfig.tcl-1
@@ -16,6 +16,18 @@ if {[info exists env(TESTSUITE_ENABLE_SITECONFIG_BROKEN)]} {
    unk_foo
 }
 
+# redefine existing modulecmd.tcl procedure to make it broken
+if {[info exists env(TESTSUITE_ENABLE_SITECONFIG_BROKEN2)]} {
+   proc pushModuleFile {str} {
+     unk_foo
+   }
+}
+
+# unset existing modulecmd.tcl procedure
+if {[info exists env(TESTSUITE_ENABLE_SITECONFIG_BROKEN3)]} {
+   rename ::pushModuleFile {}
+}
+
 # generate error with parseAccessIssue generic msg if following environment variable is set
 if {[info exists env(TESTSUITE_ENABLE_SITECONFIG_ACCESSERR)]} {
    set errorCode "Custom error code"
diff --git a/testsuite/modules.00-init/120-siteconfig.exp b/testsuite/modules.00-init/120-siteconfig.exp
index d1cc3aef..b4e832d8 100644
--- a/testsuite/modules.00-init/120-siteconfig.exp
+++ b/testsuite/modules.00-init/120-siteconfig.exp
@@ -124,6 +124,28 @@ if { $verbose > 0 } {
 unset env(TESTSUITE_ENABLE_SITECONFIG_BROKEN)
 
 
+# test siteconfig that breaks modulecmd.tcl code
+setenv_var TESTSUITE_ENABLE_SITECONFIG_BROKEN2 1
+set ans [list]
+lappend ans "$error_msgs: invalid command name \"unk_foo\""
+lappend ans {      while executing}
+lappend ans {  "unk_foo"}
+lappend ans {      (procedure "pushModuleFile" line 2)}
+lappend ans {      invoked from within}
+lappend ans {  "pushModuleFile {}"}
+lappend ans {  Please report this issue at https://github.com/cea-hpc/modules/issues}
+testouterr_cmd sh {foo} ERR [join $ans \n]
+unsetenv_var TESTSUITE_ENABLE_SITECONFIG_BROKEN2
+setenv_var TESTSUITE_ENABLE_SITECONFIG_BROKEN3 1
+set ans [list]
+lappend ans "$error_msgs: invalid command name \"pushModuleFile\""
+lappend ans {      while executing}
+lappend ans {  "pushModuleFile {}"}
+lappend ans {  Please report this issue at https://github.com/cea-hpc/modules/issues}
+testouterr_cmd sh {foo} ERR [join $ans \n]
+unsetenv_var TESTSUITE_ENABLE_SITECONFIG_BROKEN3
+
+
 # test siteconfig file raising error
 # test parseAccessIssue with custom error code by the way
 if { $verbose > 0 } {