diff --git a/tcl/modspec.tcl b/tcl/modspec.tcl
index d8efe08d..f02f8805 100644
--- a/tcl/modspec.tcl
+++ b/tcl/modspec.tcl
@@ -1490,6 +1490,12 @@ proc getModuleVersSpec {modarg} {
    }
 }
 
+proc unsetModuleVersSpec {modarg} {
+   if {[info exists ::g_moduleVersSpec($modarg)]} {
+      unset ::g_moduleVersSpec($modarg)
+   }
+}
+
 # get module name from module name and version spec if parsed
 proc getModuleNameFromVersSpec {modarg} {
    if {[info exists ::g_moduleVersSpec($modarg)]} {
diff --git a/tcl/subcmd.tcl.in b/tcl/subcmd.tcl.in
index cf34fd53..1f0d9843 100644
--- a/tcl/subcmd.tcl.in
+++ b/tcl/subcmd.tcl.in
@@ -814,6 +814,9 @@ proc cmdModuleSource {mode args} {
          set modfile $absfpath
          set modname $absfpath
          set modnamevr $absfpath
+         # unset module specification not to confuse specific char in file
+         # path (like '+') with variant specification
+         unsetModuleVersSpec $mod
          set mod $absfpath
       # if not a path specification, try to resolve a modulefile
       } elseif {![isModuleFullPath $rawarg]} {