diff --git a/configure.ac b/configure.ac
index 19930182c..76272089f 100644
--- a/configure.ac
+++ b/configure.ac
@@ -173,6 +173,9 @@ AS_IF([test "x$CRYPTO_PKG" = "x"], [
     )
 ])
 
+AM_CONDITIONAL([CRYPTO_USE_OPENSSL],[test "x$CRYPTO_PKG" = "xopenssl"])
+AM_CONDITIONAL([CRYPTO_USE_CYASSL],[test "x$CRYPTO_PKG" = "xcyassl"])
+AM_CONDITIONAL([CRYPTO_USE_POLARSSL],[test "x$CRYPTO_PKG" = "xpolarssl"])
 AC_SUBST(CRYPTO_PKG)
 AC_SUBST(CRYPTO_CFLAGS)
 AC_SUBST(CRYPTO_LIBS)
diff --git a/libtransmission/Makefile.am b/libtransmission/Makefile.am
index ae0b7c47b..a77fafbe1 100644
--- a/libtransmission/Makefile.am
+++ b/libtransmission/Makefile.am
@@ -31,7 +31,6 @@ libtransmission_a_SOURCES = \
   crypto.c \
   crypto-utils.c \
   crypto-utils-fallback.c \
-  crypto-utils-@CRYPTO_PKG@.c \
   error.c \
   fdlimit.c \
   file.c \
@@ -83,6 +82,16 @@ else
 libtransmission_a_SOURCES += file-posix.c
 endif
 
+if CRYPTO_USE_OPENSSL
+libtransmission_a_SOURCES += crypto-utils-openssl.c
+endif
+if CRYPTO_USE_CYASSL
+libtransmission_a_SOURCES += crypto-utils-cyassl.c
+endif
+if CRYPTO_USE_POLARSSL
+libtransmission_a_SOURCES += crypto-utils-polarssl.c
+endif
+
 noinst_HEADERS = \
   announcer.h \
   announcer-common.h \