Ok,
for some reason (I don't know why) Apache configuration puts in httpd.conf incorrect name of the file.
For users who will try to install Apache with PHP I discribe the steps of installation on my server (RedHat, Apache 1.3.12, PHP 4.0.0):
Apache dist. path - /tmp/install/apache_1.3.12
PHP dist. path - /tmp/install/php-4.0.0
$ cd /tmp/install/apache_1.3.12
$ ./configure --prefix=/usr/local/apache (this is for my server)
$ cd ../php-4.0.0
$ ./configure --with-apache=../apache_1.3.12 --prefix=/usr/local/php (this is for my server)
$ make
$ make install
$ cd ../apache_1.3.12
$ ./configure --prefix=/usr/local/apache --activate-module=src/modules/php4/libphp4.module (instead of libmodphp4.a file)
$ make
$ make install
Now you should check your httpd.conf file and correct names of modules.
The lines should be:
LoadModule php4_module libexec/libphp4.so
and
AddModule mod_php4.c
And at the end you should check the name of lib file in libexec folder. It should be libphp4.so instead of libmodphp4.so.
That's it!
I hope my short instruction will be useful.