diff --git a/init/modulerc.in b/init/modulerc.in
index 227016f1..81c725d5 100644
--- a/init/modulerc.in
+++ b/init/modulerc.in
@@ -1,3 +1,4 @@
+#%Module1.0
 # This file defines the initial setup for the modulefiles search path
 # and modulefiles you want to load by default for all users. It should
 # contains a lines of module command like 'module use path' and
diff --git a/modulecmd.tcl b/modulecmd.tcl
index 20770dfb..0ac5522a 100755
--- a/modulecmd.tcl
+++ b/modulecmd.tcl
@@ -33,7 +33,7 @@ echo "FATAL: module: Could not find tclsh in \$PATH or in standard directories"
 #
 # Some Global Variables.....
 #
-set MODULES_CURRENT_VERSION 1.804
+set MODULES_CURRENT_VERSION 1.807
 set MODULES_CURRENT_RELEASE_DATE "2017-04-17"
 set g_debug 0 ;# Set to 1 to enable debugging
 set error_count 0 ;# Start with 0 errors
@@ -229,7 +229,7 @@ proc unset-env {var} {
    }
 }
 
-proc execute-modulefile {modfile {exit_on_error 1}} {
+proc execute-modulefile {modfile {exit_on_error 1} {must_have_cookie 1}} {
    global g_debug g_inhibit_interp g_inhibit_errreport g_inhibit_dispreport
    global ModulesCurrentModulefile
 
@@ -287,12 +287,14 @@ proc execute-modulefile {modfile {exit_on_error 1}} {
          $g_inhibit_errreport]
       interp eval $slave [list "set" "g_inhibit_dispreport"\
          $g_inhibit_dispreport]
+      interp eval $slave [list "set" "must_have_cookie" $must_have_cookie]
    }
    set errorVal [interp eval $slave {
       if {$g_debug} {
          report "Sourcing $ModulesCurrentModulefile"
       }
-      set modcontent [readModuleContent $ModulesCurrentModulefile 1]
+      set modcontent [readModuleContent $ModulesCurrentModulefile 1\
+         $must_have_cookie]
       if {$modcontent eq ""} {
          # exit after end of slave evaluation
          return 2
@@ -2757,7 +2759,7 @@ proc checkValidModule {modfile} {
    return 0
 }
 
-proc readModuleContent {modfile {report_read_issue 0}} {
+proc readModuleContent {modfile {report_read_issue 0} {must_have_cookie 1}} {
    reportDebug "readModuleContent: $modfile"
 
    # read file
@@ -2772,8 +2774,8 @@ proc readModuleContent {modfile {report_read_issue 0}} {
       return {}
    }
 
-   # check module validity
-   if {[string first "\#%Module" $fdata] == 0} {
+   # check module validity if magic cookie is mandatory
+   if {[string first "\#%Module" $fdata] == 0 || !$must_have_cookie} {
       return $fdata
    } else {
       reportInternalBug "Magic cookie '#%Module' missing in '$modfile'"
@@ -4008,7 +4010,11 @@ proc cmdModuleSource {args} {
          pushMode "load"
          pushSpecifiedName $file
          pushModuleName $file
-         execute-modulefile $file
+         # relax constraint of having a magic cookie at the start of the
+         # modulefile to execute as sourced files may need more flexibility
+         # as they may be managed outside of the modulefile environment like
+         # the initialization modulerc file
+         execute-modulefile $file 1 0
          popModuleName
          popSpecifiedName
          popMode
diff --git a/testsuite/home/rcnomagic b/testsuite/home/rcnomagic
new file mode 100644
index 00000000..f44d7559
--- /dev/null
+++ b/testsuite/home/rcnomagic
@@ -0,0 +1,22 @@
+#%Missing magic cookie
+
+##############################################################################
+#   Modules Revision 3.0
+#   Providing a flexible user environment
+#
+#   File:		home/%M%
+#   Revision:		%I%
+#   First Edition:	2017/04/17
+#   Last Mod.:		%U%, %G%
+#
+#   Authors:		Xavier Delaruelle, xavier.delaruelle@cea.fr
+#
+#   Description:	RC file to source
+#
+#   Comment:	%C{
+#			RC file to test behavior of module command 'source'
+#		}C%
+#
+##############################################################################
+
+setenv testsuite "yes"
diff --git a/testsuite/home/rctosource b/testsuite/home/rctosource
new file mode 100644
index 00000000..7b9edeca
--- /dev/null
+++ b/testsuite/home/rctosource
@@ -0,0 +1,22 @@
+#%Module1.0
+
+##############################################################################
+#   Modules Revision 3.0
+#   Providing a flexible user environment
+#
+#   File:		home/%M%
+#   Revision:		%I%
+#   First Edition:	2017/04/17
+#   Last Mod.:		%U%, %G%
+#
+#   Authors:		Xavier Delaruelle, xavier.delaruelle@cea.fr
+#
+#   Description:	RC file to source
+#
+#   Comment:	%C{
+#			RC file to test behavior of module command 'source'
+#		}C%
+#
+##############################################################################
+
+setenv testsuite "yes"
diff --git a/testsuite/modules.70-maint/090-source.exp b/testsuite/modules.70-maint/090-source.exp
new file mode 100644
index 00000000..2e3866c5
--- /dev/null
+++ b/testsuite/modules.70-maint/090-source.exp
@@ -0,0 +1,60 @@
+##############################################################################
+#   Modules Revision 3.0
+#   Providing a flexible user environment
+#
+#   File:		modules.70-maint/%M%
+#   Revision:		%I%
+#   First Edition:	2017/04/17
+#   Last Mod.:		%U%, %G%
+#
+#   Authors:		Xavier Delaruelle, xavier.delaruelle@cea.fr
+#
+#   Description:	Testuite testsequence
+#   Command:		source
+#   Modulefiles:	rctosource, rcnomagic, nonexistent
+#   Sub-Command:
+#
+#   Comment:	%C{
+#			Tests the module command 'source'
+#		}C%
+#
+##############################################################################
+
+#
+#  Test variables
+#
+
+set module_1 "$env(TESTSUITEDIR)/home/rctosource"
+set module_2 "$env(TESTSUITEDIR)/home/rcnomagic"
+set module_3 "$env(TESTSUITEDIR)/home/nonexistent"
+
+set out_csh "setenv testsuite yes;"
+set out_csh3 "/bin/false;"
+set err_csh "$error_msgs: File $module_3 does not exist"
+
+#
+#  test sourcing rc file with regular module-specific magic cookie
+#
+testouterr_cmd "csh" "source $module_1" "$out_csh" ""
+
+#
+#  test sourcing rc file with no module-specific magic cookie
+#
+testouterr_cmd "csh" "source $module_2" "$out_csh" ""
+
+#
+# test with nonexistent file
+#
+testouterr_cmd "csh" "source $module_3" "$out_csh3" "$err_csh"
+
+#
+#  Cleanup
+#
+
+unset err_csh
+unset out_csh3
+unset out_csh
+
+unset module_1
+unset module_2
+unset module_3