Subversion : some progress

Disclaimer: I'm new to ReadyNAS and linux.
I'm trying this with the latest subversion 1.5.1 files. This is what I've done so far:

1. started with a fresh factory default ReadyNAS (RAIDiator 4.1.3-T136 [1.00a146] in X-RAID)
2. downloaded EnableRootSSH and APT from here
3. installed those .bin files via FrontView, System>Update>Local
4. logged into my ReadyNAS via SSH (putty)
5. apt-get update
6. apt-get install nano (I'm not a vi wizard)
7. apt-get install gcc
8. wget http://subversion.tigris.org/downloads/subversion-1.5.1.tar.gz
9. wget http://subversion.tigris.org/downloads/subversion-deps-1.5.1.tar.gz
10. tar xvzf subversion-1.5.1.tar.gz
11. tar xvzf subversion-deps-1.5.1.tar.gz
12. rm *.gz (why keep the tarballs?)
13. cd subversion-1.5.1/zlib/
14. ./configure && make test && make install

This is where I get stuck. Here is the error dump:

Checking for gcc...
Building static library libz.a version 1.2.3 with gcc.
Checking for unistd.h... No.
Checking whether to use vs[n]printf() or s[n]printf()... using s[n]printf()
Checking for snprintf() in stdio.h... No.
  WARNING: snprintf() not found, falling back to sprintf(). zlib
  can build but will be open to possible buffer-overflow security
  vulnerabilities.
Checking for return value of sprintf()... No.
  WARNING: apparently sprintf() does not return a value. zlib
  can build but will be open to possible string-format security
  vulnerabilities.
Checking for errno.h... No.
Checking for mmap support... No.
gcc -O3 -DNO_snprintf -DHAS_sprintf_void -DNO_ERRNO_H   -c -o example.o example.c
example.c:8:19: stdio.h: No such file or directory
example.c:12:22: string.h: No such file or directory
example.c:13:22: stdlib.h: No such file or directory
example.c: In function `test_compress':
example.c:67: error: `stderr' undeclared (first use in this function)
example.c:67: error: (Each undeclared identifier is reported only once
example.c:67: error: for each function it appears in.)
example.c: In function `test_gzio':
example.c:99: error: `NULL' undeclared (first use in this function)
example.c:100: error: `stderr' undeclared (first use in this function)
example.c: In function `test_deflate':
example.c:182: error: `stderr' undeclared (first use in this function)
example.c: In function `test_inflate':
example.c:225: error: `stderr' undeclared (first use in this function)
example.c: In function `test_large_deflate':
example.c:260: error: `stderr' undeclared (first use in this function)
example.c: In function `test_large_inflate':
example.c:320: error: `stderr' undeclared (first use in this function)
example.c: In function `test_flush':
example.c:357: error: `stderr' undeclared (first use in this function)
example.c: In function `test_sync':
example.c:399: error: `stderr' undeclared (first use in this function)
example.c: In function `test_dict_deflate':
example.c:438: error: `stderr' undeclared (first use in this function)
example.c: In function `test_dict_inflate':
example.c:480: error: `stderr' undeclared (first use in this function)
example.c: In function `main':
example.c:524: error: `stderr' undeclared (first use in this function)
make: *** [example.o] Error 1

Any ideas what I'm missing? It looks like I'm missing some important header files (stdio, string, stdlib). How do I get those? And where do I put them?

Also, if I can get the above working and continue on with the subversion installation, what are the steps needed to replace /dev/random with /dev/urandom in apr?

zfil? rocket15? Bueller? Anyone?

Much thanks!