diff --git a/doc/internals/http-parsing.txt b/doc/internals/http-parsing.txt
index fd41b6e..494558b 100644
--- a/doc/internals/http-parsing.txt
+++ b/doc/internals/http-parsing.txt
@@ -212,6 +212,102 @@
 recognizable by the recipient. Unrecognized header fields SHOULD be ignored by
 the recipient and MUST be forwarded by transparent proxies.
 
+----------------------------------
+
+The format of Request-URI is defined by RFC3986 :
+
+   URI           = scheme ":" hier-part [ "?" query ] [ "#" fragment ]
+
+   hier-part     = "//" authority path-abempty
+                 / path-absolute
+                 / path-rootless
+                 / path-empty
+
+   URI-reference = URI / relative-ref
+
+   absolute-URI  = scheme ":" hier-part [ "?" query ]
+
+   relative-ref  = relative-part [ "?" query ] [ "#" fragment ]
+
+   relative-part = "//" authority path-abempty
+                 / path-absolute
+                 / path-noscheme
+                 / path-empty
+
+   scheme        = ALPHA *( ALPHA / DIGIT / "+" / "-" / "." )
+
+   authority     = [ userinfo "@" ] host [ ":" port ]
+   userinfo      = *( unreserved / pct-encoded / sub-delims / ":" )
+   host          = IP-literal / IPv4address / reg-name
+   port          = *DIGIT
+
+   IP-literal    = "[" ( IPv6address / IPvFuture  ) "]"
+
+   IPvFuture     = "v" 1*HEXDIG "." 1*( unreserved / sub-delims / ":" )
+
+   IPv6address   =                            6( h16 ":" ) ls32
+                 /                       "::" 5( h16 ":" ) ls32
+                 / [               h16 ] "::" 4( h16 ":" ) ls32
+                 / [ *1( h16 ":" ) h16 ] "::" 3( h16 ":" ) ls32
+                 / [ *2( h16 ":" ) h16 ] "::" 2( h16 ":" ) ls32
+                 / [ *3( h16 ":" ) h16 ] "::"    h16 ":"   ls32
+                 / [ *4( h16 ":" ) h16 ] "::"              ls32
+                 / [ *5( h16 ":" ) h16 ] "::"              h16
+                 / [ *6( h16 ":" ) h16 ] "::"
+
+   h16           = 1*4HEXDIG
+   ls32          = ( h16 ":" h16 ) / IPv4address
+   IPv4address   = dec-octet "." dec-octet "." dec-octet "." dec-octet
+   dec-octet     = DIGIT                 ; 0-9
+                 / %x31-39 DIGIT         ; 10-99
+                 / "1" 2DIGIT            ; 100-199
+                 / "2" %x30-34 DIGIT     ; 200-249
+                 / "25" %x30-35          ; 250-255
+
+   reg-name      = *( unreserved / pct-encoded / sub-delims )
+
+   path          = path-abempty    ; begins with "/" or is empty
+                 / path-absolute   ; begins with "/" but not "//"
+                 / path-noscheme   ; begins with a non-colon segment
+                 / path-rootless   ; begins with a segment
+                 / path-empty      ; zero characters
+
+   path-abempty  = *( "/" segment )
+   path-absolute = "/" [ segment-nz *( "/" segment ) ]
+   path-noscheme = segment-nz-nc *( "/" segment )
+   path-rootless = segment-nz *( "/" segment )
+   path-empty    = 0<pchar>
+
+   segment       = *pchar
+   segment-nz    = 1*pchar
+   segment-nz-nc = 1*( unreserved / pct-encoded / sub-delims / "@" )
+                 ; non-zero-length segment without any colon ":"
+
+   pchar         = unreserved / pct-encoded / sub-delims / ":" / "@"
+
+   query         = *( pchar / "/" / "?" )
+
+   fragment      = *( pchar / "/" / "?" )
+
+   pct-encoded   = "%" HEXDIG HEXDIG
+
+   unreserved    = ALPHA / DIGIT / "-" / "." / "_" / "~"
+   reserved      = gen-delims / sub-delims
+   gen-delims    = ":" / "/" / "?" / "#" / "[" / "]" / "@"
+   sub-delims    = "!" / "$" / "&" / "'" / "(" / ")"
+                 / "*" / "+" / "," / ";" / "="
+
+=> so the list of allowed characters in a URI is :
+
+   uri-char      = unreserved / gen-delims / sub-delims / "%"
+                 = ALPHA / DIGIT / "-" / "." / "_" / "~"
+                 / ":" / "/" / "?" / "#" / "[" / "]" / "@"
+                 / "!" / "$" / "&" / "'" / "(" / ")" /
+                 / "*" / "+" / "," / ";" / "=" / "%"
+
+Note that non-ascii characters are forbidden ! Spaces and CTL are forbidden.
+Unfortunately, some products such as Apache allow such characters :-/
+
 ---- The correct way to do it ----
 
 - one http_session