diff --git a/external/subpack/mail/sendmail/files/OpenWrt b/external/subpack/mail/sendmail/files/OpenWrt
new file mode 100644
index 0000000..c0a01a9
--- /dev/null
+++ b/external/subpack/mail/sendmail/files/OpenWrt
@@ -0,0 +1,61 @@
+dnl	DO NOT EDIT THIS FILE.
+dnl	Place personal settings in devtools/Site/site.config.m4
+
+define(`confDEPEND_TYPE', `CC-M')
+define(`confCCOPTS_SO', `-fPIC')
+define(`confSM_OS_HEADER', `sm_os_linux')
+define(`confLIBS', `-ldl')
+define(`confEBINDIR', `/usr/sbin')
+define(`confMKDIR', `mkdir')
+define(`confLIBSEARCHPATH', `STAGING_DIR/lib STAGING_DIR/usr/lib')
+APPENDDEF(`confLIBSEARCH', `crypt')
+
+define(`confMTCCOPTS', `-D_REENTRANT')
+define(`confMTLDOPTS', `-lpthread')
+define(`confLDOPTS_SO', `-shared')
+define(`confSONAME',`-Wl,-soname')
+
+define(`currentuser', esyscmd(`id -nu'))
+define(`currentgroup', esyscmd(`id -ng'))
+
+define(`confDONT_INSTALL_CATMAN',)
+define(`confNO_MAN_BUILD',)
+define(`confINCOWN', currentuser)
+define(`confINCGRP', currentgroup)
+define(`confINCMODE', `644')
+define(`confLIBOWN', currentuser)
+define(`confLIBGRP', currentgroup)
+define(`confLIBMODE', `644')
+define(`confMBINOWN', currentuser)
+define(`confMBINGRP', currentgroup)
+define(`confMBINMODE', `750')
+define(`confSBINOWN', currentuser)
+define(`confSBINGRP', currentgroup)
+define(`confSBINMODE', `755')
+define(`confUBINOWN', currentuser)
+define(`confUBINGRP', currentgroup)
+define(`confUBINMODE', `755')
+define(`confGBINOWN', currentuser)
+define(`confGBINGRP', currentgroup)
+define(`confGBINMODE', `755')
+define(`confMSPQOWN', currentuser)
+
+ifelse(confBLDVARIANT, `DEBUG',
+dnl Debug build
+`
+	define(`confOPTIMIZE',`-g -Wall')
+',
+dnl Optimized build
+confBLDVARIANT, `OPTIMIZED',
+`
+	define(`confOPTIMIZE',`-O2')
+',
+dnl Purify build
+confBLDVARIANT, `PURIFY',
+`
+	define(`confOPTIMIZE',`-g')
+',
+dnl default
+`
+	define(`confOPTIMIZE',`-O2')
+')