diff --git a/Pmodules/libpbuild.bash b/Pmodules/libpbuild.bash
index 3404b63..50f5687 100644
--- a/Pmodules/libpbuild.bash
+++ b/Pmodules/libpbuild.bash
@@ -1302,7 +1302,7 @@ pbuild.build_module() {
 	build_dependency() {
 		local -r m=$1
 		std::debug "${m}: module not available"
-		local rels=( ${PMODULES_DEFINED_RELEASES//:/ } )
+		local rels=( ${ReleaseStages//:/ } )
 		[[ ${dry_run} == yes ]] && \
 			std::die 1 \
 				 "%s " \
diff --git a/Pmodules/modulecmd.bash.in b/Pmodules/modulecmd.bash.in
index 799ee94..37dc83e 100644
--- a/Pmodules/modulecmd.bash.in
+++ b/Pmodules/modulecmd.bash.in
@@ -38,7 +38,7 @@ fi
 
 source "${libdir}/libstd.bash"
 
-: ${PMODULES_DEFINED_RELEASES:=':unstable:stable:deprecated:'}
+: ${ReleaseStages:=':unstable:stable:deprecated:'}
 
 declare -r  version='@PMODULES_VERSION@'
 
@@ -103,8 +103,8 @@ declare g_env_must_be_saved='no'
 save_env() {
         [[ $1 == 'no' ]] && return 0
         local vars=( Version GroupDepths UsedReleases UseFlags UsedGroups )
-        vars+=( PMODULES_DEFAULT_GROUPS PMODULES_DEFINED_RELEASES )
-        vars+=( PMODULES_DEFAULT_RELEASES )
+        vars+=( PMODULES_DEFAULT_GROUPS ReleaseStages )
+        vars+=( DefaultUsedReleaseStages )
 
 	local s=$(typeset -p ${vars[@]})
 	declare -g PMODULES_ENV=$( "${base64}" --wrap=0 <<< "$s" )
@@ -151,7 +151,7 @@ get_release() {
 }
 
 is_release() {
-	[[ ${PMODULES_DEFINED_RELEASES} =~ :$1: ]]
+	[[ ${ReleaseStages} =~ :$1: ]]
 }
 
 #
@@ -937,7 +937,7 @@ subcommand_avail() {
                                 print_help "${subcommand}"
                                 ;;
 			-a | --all | --all-releases )
-				opt_use_releases="${PMODULES_DEFINED_RELEASES}"
+				opt_use_releases="${ReleaseStages}"
 				;;
 			-h | --human )
 				output_function='human_readable_output'
@@ -1095,7 +1095,7 @@ subcommand_use() {
 			std::info "\t${r}"
 		done
 		std::info "\nUnused releases:"
-		for r in ${PMODULES_DEFINED_RELEASES//:/ }; do
+		for r in ${ReleaseStages//:/ }; do
 			if ! release_is_used $r; then
 				std::info "\t${r}"
 			fi
@@ -1371,7 +1371,7 @@ reset_used_groups() {
 
 reset_used_releases() {
 	declare -g  UsedReleases=''
-	for r in ${PMODULES_DEFAULT_RELEASES//:/ }; do
+	for r in ${DefaultUsedReleaseStages//:/ }; do
 		std::append_path UsedReleases "${r}"
 	done
         g_env_must_be_saved='yes'
@@ -1916,7 +1916,7 @@ subcommand_search() {
                                 done
 				;;
 			-a | --all-releases )
-				opt_use_releases="${PMODULES_DEFINED_RELEASES}"
+				opt_use_releases="${ReleaseStages}"
 				;;
 			--src )
 				# :FIXME: do we have to add some sanity checks here?
diff --git a/Pmodules/profile.bash.in b/Pmodules/profile.bash.in
index 3cc380c..851d5b8 100644
--- a/Pmodules/profile.bash.in
+++ b/Pmodules/profile.bash.in
@@ -7,7 +7,7 @@
 : ${PMODULES_DEFAULT_GROUPS:='Tools Programming'}
 
 # set releases which should be available after initialization
-: ${PMODULES_DEFAULT_RELEASES:='stable'}
+: ${DefaultUsedReleaseStages:='stable'}
 
 # set default version
 : ${PMODULES_VERSION:=@PMODULES_VERSION@}
@@ -23,11 +23,11 @@
 #
 
 export	PMODULES_DEFAULT_GROUPS
-export	PMODULES_DEFAULT_RELEASES
+export	DefaultUsedReleaseStages
 export	PMODULES_VERSION
 
 declare -x PMODULES_MODULEFILES_DIR='modulefiles'
-declare -x PMODULES_DEFINED_RELEASES=':unstable:stable:deprecated:'
+declare -x ReleaseStages=':unstable:stable:deprecated:'
 
 declare -x PMODULES_ROOT=$(cd $(dirname "${BASH_SOURCE}")/.. && pwd)
 declare -x PMODULES_CONFIG_DIR=$(basename $(cd $(dirname "${BASH_SOURCE}") && pwd))
diff --git a/Pmodules/profile.csh.in b/Pmodules/profile.csh.in
index 0047bdb..5baa5c4 100755
--- a/Pmodules/profile.csh.in
+++ b/Pmodules/profile.csh.in
@@ -1,7 +1,7 @@
 #!/bin/tcsh
 
 setenv PMODULES_DEFAULT_GROUPS 'Tools Programming'
-setenv PMODULES_DEFAULT_RELEASES 'stable'
+setenv DefaultUsedReleaseStages 'stable'
 if ( ! $?PMODULES_VERSION ) then
 	setenv PMODULES_VERSION "@PMODULES_VERSION@"
 endif
@@ -14,7 +14,7 @@ endif
 #############################################################################
 
 setenv PMODULES_MODULEFILES_DIR 'modulefiles'
-setenv PMODULES_DEFINED_RELEASES ':unstable:stable:deprecated:'
+setenv ReleaseStages ':unstable:stable:deprecated:'
 
 setenv PMODULES_ROOT "@PMODULES_ROOT@"
 setenv PMODULES_CONFIG_DIR 'config'
diff --git a/Pmodules/profile.zsh.in b/Pmodules/profile.zsh.in
index 83a2ac9..b8bb938 100644
--- a/Pmodules/profile.zsh.in
+++ b/Pmodules/profile.zsh.in
@@ -8,11 +8,11 @@
 #
 
 declare -xa PMODULES_DEFAULT_GROUPS
-declare -xa PMODULES_DEFAULT_RELEASES
+declare -xa DefaultUsedReleaseStages
 declare -x  PMODULES_VERSION
 
 : ${PMODULES_DEFAULT_GROUPS:=(Tools Programming)}
-: ${PMODULES_DEFAULT_RELEASES:=(stable)}
+: ${DefaultUsedReleaseStages:=(stable)}
 : ${PMODULES_VERSION:=@PMODULES_VERSION@}
 
 #############################################################################
@@ -20,7 +20,7 @@ declare -x  PMODULES_VERSION
 #############################################################################
 
 declare -x PMODULES_MODULEFILES_DIR='modulefiles'
-declare -x PMODULES_DEFINED_RELEASES=':unstable:stable:deprecated:'
+declare -x ReleaseStages=':unstable:stable:deprecated:'
 
 declare -x PMODULES_ROOT=$(cd $(dirname "${(%):-%N}")/.. && pwd)
 declare -x PMODULES_CONFIG_DIR=$(basename $(cd $(dirname "${(%):-%N}") && pwd))
diff --git a/Pmodules/zsh b/Pmodules/zsh
index 80dc338..2fda058 100644
--- a/Pmodules/zsh
+++ b/Pmodules/zsh
@@ -78,16 +78,16 @@ done
 # build initial list of used releases
 declare -x UsedReleases=''
 typeset -T UsedReleases usedreleases
-for r in ${PMODULES_DEFAULT_RELEASES[@]}; do
+for r in ${DefaultUsedReleaseStages[@]}; do
 	usedreleases=( "${r}" ${(m)usedreleases:#${r}} )
 done
 
-eval $(save_env UsedReleases PMODULES_DEFAULT_RELEASES PMODULES_DEFAULT_GROUPS PMODULES_DEFINED_RELEASES)
+eval $(save_env UsedReleases DefaultUsedReleaseStages PMODULES_DEFAULT_GROUPS ReleaseStages)
 
 unset UsedReleases
-unset PMODULES_DEFAULT_RELEASES
+unset DefaultUsedReleaseStages
 unset PMODULES_DEFAULT_GROUPS
-unset PMODULES_DEFINED_RELEASES
+unset ReleaseStages
 
 # initialize MANPATH with output of `man --path` if not set
 [[ -z "${MANPATH}" ]] && manpath=$( man --path )
diff --git a/config/modbuild.conf.in b/config/modbuild.conf.in
index 60d33c3..5c28cd9 100644
--- a/config/modbuild.conf.in
+++ b/config/modbuild.conf.in
@@ -13,6 +13,6 @@ declare -x PMODULES_MODULEFILES_DIR='modulefiles'
 declare -x PMODULES_HOME="${PMODULES_ROOT}/Tools/Pmodules/${PMODULES_VERSION}"
 
 declare -x PMODULES_DEFAULT_GROUPS='Tools Programming'
-declare -x PMODULES_DEFINED_RELEASES=':unstable:stable:deprecated:'
-declare -x PMODULES_DEFAULT_RELEASES='stable'
+declare    ReleaseStages=':unstable:stable:deprecated:'
+declare    DefaultUsedReleaseStages='stable'