Shell .profile or /etc/profile for old android 2.3.3

Just rooted my old phone with Android 2.3.3 and I would like to define some aliases for each shell I start (with adb or terminal app). I found this question where one answer says that /etc/profile (=/system/etc/profile due to soft link /etc->/system/etc) is one of the files the shell sources on startup. But this post talks about /system/bin/sh being a link to /system/bin/mksh, which is not the case on my 2.3.3 system. Despite the fact that strings sh produces /etc/profile as one output, the file is not sourced. Does anyone happen to know the old Android version and whether I have a chance to get /etc/profile or some other file sourced on shell startup? I thought it might be a permission problem but even rwxrwxr-x does not help.