diff --git a/conf/packages/packages.server.qa.exec.example b/conf/packages/packages.server.qa.exec.example
old mode 100644
new mode 100755
index 21079976f..ffb487f33
--- a/conf/packages/packages.server.qa.exec.example
+++ b/conf/packages/packages.server.qa.exec.example
@@ -7,8 +7,9 @@
 #
 # It is used by Entropy Server QA routines to perform package metadata
 # validation.
-# Metadata is export in environmental variables form, and include:
+# Metadata is exported as environmental variables and stdin.
 #
+# Metadata from environment:
 # REPOSITORY_ID = repository identifier
 # PKG_ID = package identifier
 # PKG_ATOM = package atom
@@ -32,13 +33,17 @@
 # PKG_SIZE = package size, in bytes
 # PKG_REVISION = package entropy revision
 # PKG_DEPS = list (\n separated) of package dependencies and conflicts
-# PKG_NEEDED_LIBS = list (\n separated) of SONAMES required by package,
-#    including ELF class, so each item will look like this:
-#     <soname>|<elfclass>
-# PKG_PROVIDED_LIBS = list (\n separated) of SONAMES provided by package,
-#    note: elf class and path are also provided,
-#    so each item will look like this:
-#     <soname>|<path of soname>|<elfclass>
+
+# Metadata on stdin (more can be added in the future, so it's advisable
+# to ignore entries well formed but with unknown prefix):
+# PKG_NEEDED_LIB:
+#	SONAME required by package (one per line), including ELF class,
+#	so each line will look like this:
+#     PKG_NEEDED_LIB|<soname>|<elfclass>
+# PKG_PROVIDED_LIB:
+#	SONAME provided by package (one per line), note: elf class
+#	and path are also provided, so each line will look like this:
+#     PKG_PROVIDED_LIB|<soname>|<path of soname>|<elfclass>
 #
 # The executable must return 0 for success, 1 for warning, 2 for critical error
 
@@ -67,8 +72,12 @@ echo "PKG_DATE = ${PKG_DATE}"
 echo "PKG_SIZE = ${PKG_SIZE}"
 echo "PKG_REVISION = ${PKG_REVISION}"
 echo "PKG_DEPS = ${PKG_DEPS}"
-echo "PKG_NEEDED_LIBS = ${PKG_NEEDED_LIBS}"
-echo "PKG_PROVIDED_LIBS = ${PKG_PROVIDED_LIBS}"
+
+stdin=$(cat)
+echo "PKG_NEEDED_LIB = "
+echo "${stdin}" | sed -n 's/^PKG_NEEDED_LIB|//p'
+echo "PKG_PROVIDED_LIB = "
+echo "${stdin}" | sed -n 's/^PKG_PROVIDED_LIB|//p'
 echo
 
-exit 0
\ No newline at end of file
+exit 0
diff --git a/lib/entropy/server/interfaces/main.py b/lib/entropy/server/interfaces/main.py
index 8f43069a3..28fb49807 100644
--- a/lib/entropy/server/interfaces/main.py
+++ b/lib/entropy/server/interfaces/main.py
@@ -6664,18 +6664,22 @@ class Server(Client):
             env['PKG_SIZE'] = str(pkg_size)
             env['PKG_REVISION'] = str(pkg_rev)
             env['PKG_DEPS'] = str("\n".join(pkg_deps))
-            env['PKG_NEEDED_LIBS'] = str("\n".join(
-                    ["%s|%s|%s|%s|%s" % (a, b, x, y, c) for a, b, x, y, c in
-                     pkg_needed]))
-            env['PKG_PROVIDED_LIBS'] = str("\n".join(
-                ["%s|%s|%s" % (x, y, z) for x, y, z in \
-                    pkg_provided_libs]))
+
+            # These two are not exposed in environment because they can be large;
+            # avoid "Argument list too long."
+            stdin_lines = []
+            stdin_lines += ["PKG_NEEDED_LIB|%s|%s|%s|%s|%s" % (a, b, x, y, c) \
+                            for a, b, x, y, c in pkg_needed]
+            stdin_lines += ["PKG_PROVIDED_LIB|%s|%s|%s" % (x, y, z) \
+                            for x, y, z in pkg_provided_libs]
+            stdin = const_convert_to_rawstring("\n".join(stdin_lines))
 
             # now call the script
             try:
                 proc = subprocess.Popen(
                     [qa_exec], stdout = sys.stdout, stderr = sys.stderr,
-                    stdin = sys.stdin, env = env)
+                    stdin = subprocess.PIPE, env = env)
+                proc.communicate(input=stdin)
                 rc = proc.wait()
             except OSError as err:
                 self.output(