diff --git a/configure b/configure
index 1e7b9f7a..ef81e71b 100755
--- a/configure
+++ b/configure
@@ -26,6 +26,11 @@ readonly DEFAULT_IFS="$IFS"
 srcdir=$(dirname "$0")
 NOTMUCH_SRCDIR=$(cd "$srcdir" && pwd)
 
+case $NOTMUCH_SRCDIR in ( *\'* | *['\"`$']* )
+	echo "Definitely unsafe characters in source path '$NOTMUCH_SRCDIR'".
+	exit 1
+esac
+
 subdirs="util compat lib parse-time-string completion doc emacs"
 subdirs="${subdirs} performance-test test test/test-databases"
 subdirs="${subdirs} bindings"
@@ -513,7 +518,7 @@ int main () {
 
     g_mime_init ();
     parser = g_mime_parser_new ();
-    g_mime_parser_init_with_stream (parser, g_mime_stream_file_open("test/corpora/crypto/basic-encrypted.eml", "r", &error));
+    g_mime_parser_init_with_stream (parser, g_mime_stream_file_open("$srcdir/test/corpora/crypto/basic-encrypted.eml", "r", &error));
     if (error) return !! fprintf (stderr, "failed to instantiate parser with test/corpora/crypto/basic-encrypted.eml\n");
 
     body = GMIME_MULTIPART_ENCRYPTED(g_mime_message_get_mime_part (g_mime_parser_construct_message (parser, NULL)));
@@ -533,7 +538,7 @@ EOF
         printf 'No.\nCould not make tempdir for testing session-key support.\n'
         errors=$((errors + 1))
     elif ${CC} ${CFLAGS} ${gmime_cflags} _check_session_keys.c ${gmime_ldflags} -o _check_session_keys \
-           && GNUPGHOME=${TEMP_GPG} gpg --batch --quiet --import < test/gnupg-secret-key.asc \
+           && GNUPGHOME=${TEMP_GPG} gpg --batch --quiet --import < "$srcdir"/test/gnupg-secret-key.asc \
            && SESSION_KEY=$(GNUPGHOME=${TEMP_GPG} ./_check_session_keys) \
            && [ $SESSION_KEY = 9:0BACD64099D1468AB07C796F0C0AC4851948A658A15B34E803865E9FC635F2F5 ]
     then