Why Linux Firefox doesn't play flash movies?

[Yuri]

In order to enable Flash I installed linux-firefox-devel-3.5.7 and 
linux-f10-flashplugin-10.0r45.
They together pulled whole lot of other ports, see list below.

But flash still doesn't work: youtube.com shows black windows instead.
I tried windows firefox under wine, but it has a lot of side-effects, 
since wine is perpetually buggy.

Anybody is able to play flash movies?

Thanks,
Yuri


List of all linux ports installed:
linux-dri-7.4_1     Mesa-based DRI libraries, drivers and binaries 
(Linux Ubunt
linux-f10-alsa-lib-1.0.21_1 The Advanced Linux Sound Architecture 
libraries (Linux Fedo
linux-f10-atk-1.24.0 Accessibility Toolkit, Linux/i386 binary (Linux 
Fedora 10)
linux-f10-cairo-1.8.0 Vector graphics library Cairo (Linux Fedora 10)
linux-f10-curl-7.19.6 The command line tool for transferring files with 
URL synta
linux-f10-cyrus-sasl2-2.1.22 RFC 2222 SASL (Simple Authentication and 
Security Layer) (L
linux-f10-dbus-glib-0.76 GLib bindings for D-Bus (Linux Fedora 10)
linux-f10-dbus-libs-1.2.4 Libraries for accessing D-BUS (Linux Fedora 10)
linux-f10-expat-2.0.1 Linux/i386 binary port of Expat XML-parsing 
library (Linux
linux-f10-flashplugin-10.0r45 Adobe Flash Player NPAPI Plugin
linux-f10-fontconfig-2.6.0 An XML-based font configuration API for X 
Windows (Linux Fe
linux-f10-gdk-pixbuf-0.22.0 Image loading library for GTK+ (Linux Fedora 10)
linux-f10-gtk2-2.14.7 GTK+ library, version 2.X (Linux Fedora 10)
linux-f10-hicolor-icon-theme-0.5 A high-color icon theme shell from the 
FreeDesktop project
linux-f10-jpeg-6b   RPM of the JPEG lib (Linux Fedora 10)
linux-f10-libsigc++20-2.2.2 Callback Framework for C++ (Linux Fedora 10)
linux-f10-libssh2-0.18 The library implementing the SSH2 protocol (Linux 
Fedora 10
linux-f10-libxml2-2.7.3_2 Library providing XML and HTML support (Linux 
Fedora 10)
linux-f10-nspr-4.7.6 Netscape Portable Runtime (Linux Fedora 10)
linux-f10-nss-3.12.2.0 Network Security Services (Linux Fedora 10)
linux-f10-openldap-2.4.12_1 Lightweight Directory Access Protocol 
libraries (Linux Fedo
linux-f10-openssl-0.9.8g The OpenSSL toolkit (Linux Fedora 10)
linux-f10-pango-1.22.3 The pango library (Linux Fedora 10)
linux-f10-png-1.2.37 RPM of the PNG lib (Linux Fedora 10)
linux-f10-sqlite3-3.5.9_1 The library that implements an embeddable SQL 
database engi
linux-f10-tiff-3.8.2 The TIFF library, Linux/i386 binary (Linux Fedora 10)
linux-f10-xorg-libs-7.4_1 Xorg libraries (Linux Fedora 10)
linux-firefox-devel-3.5.7 Web browser based on the browser portion of 
Mozilla
linux-nvu-1.0_1     A complete Web Authoring System
linux_base-f10-10_2 Base set of packages needed in Linux mode for 
i386/amd64 (L